### Godot version

4.0.dev Beta 14

### System information

Windows 10 and Linux (Pop!_OS 22.04)

### Issue description

When opening a UTF-8 text file with an emoji or other unicode character, the line will not show up and the editor starts producing a number of errors in output. Here is the output:

--- GDScript language server started ---
  U_ILLEGAL_ARGUMENT_ERROR
  modules/text_server_adv/text_server_adv.cpp:4389 - Condition "!sd" is true. Returning: 0.0
  modules/text_server_adv/text_server_adv.cpp:3837 - Condition "!sd" is true. Returning: TextServer::ORIENTATION_HORIZONTAL
  modules/text_server_adv/text_server_adv.cpp:5803 - Condition "!sd" is true. Returning: Size2()
  modules/text_server_adv/text_server_adv.cpp:5803 - Condition "!sd" is true. Returning: Size2()
  modules/text_server_adv/text_server_adv.cpp:5803 - Condition "!sd" is true. Returning: Size2()
  modules/text_server_adv/text_server_adv.cpp:3837 - Condition "!sd" is true. Returning: TextServer::ORIENTATION_HORIZONTAL
  modules/text_server_adv/text_server_adv.cpp:5741 - Condition "!sd" is true. Returning: 0
  modules/text_server_adv/text_server_adv.cpp:5730 - Condition "!sd" is true. Returning: nullptr
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:3837 - Condition "!sd" is true. Returning: TextServer::ORIENTATION_HORIZONTAL
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5818 - Condition "!sd" is true. Returning: 0.0
  modules/text_server_adv/text_server_adv.cpp:5829 - Condition "!sd" is true. Returning: 0.0
  modules/text_server_adv/text_server_adv.cpp:5741 - Condition "!sd" is true. Returning: 0
  modules/text_server_adv/text_server_adv.cpp:5730 - Condition "!sd" is true. Returning: nullptr
  U_ILLEGAL_ARGUMENT_ERROR
  modules/text_server_adv/text_server_adv.cpp:4389 - Condition "!sd" is true. Returning: 0.0
  modules/text_server_adv/text_server_adv.cpp:3837 - Condition "!sd" is true. Returning: TextServer::ORIENTATION_HORIZONTAL
  modules/text_server_adv/text_server_adv.cpp:5803 - Condition "!sd" is true. Returning: Size2()
  modules/text_server_adv/text_server_adv.cpp:5803 - Condition "!sd" is true. Returning: Size2()
  modules/text_server_adv/text_server_adv.cpp:5803 - Condition "!sd" is true. Returning: Size2()
  modules/text_server_adv/text_server_adv.cpp:3837 - Condition "!sd" is true. Returning: TextServer::ORIENTATION_HORIZONTAL
  modules/text_server_adv/text_server_adv.cpp:5803 - Condition "!sd" is true. Returning: Size2()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5730 - Condition "!sd" is true. Returning: nullptr
  modules/text_server_adv/text_server_adv.cpp:5741 - Condition "!sd" is true. Returning: 0
  modules/text_server_adv/text_server_adv.cpp:5818 - Condition "!sd" is true. Returning: 0.0
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5803 - Condition "!sd" is true. Returning: Size2()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5730 - Condition "!sd" is true. Returning: nullptr
  modules/text_server_adv/text_server_adv.cpp:5741 - Condition "!sd" is true. Returning: 0
  modules/text_server_adv/text_server_adv.cpp:5818 - Condition "!sd" is true. Returning: 0.0
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5803 - Condition "!sd" is true. Returning: Size2()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5730 - Condition "!sd" is true. Returning: nullptr
  modules/text_server_adv/text_server_adv.cpp:5741 - Condition "!sd" is true. Returning: 0
  modules/text_server_adv/text_server_adv.cpp:5818 - Condition "!sd" is true. Returning: 0.0
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5803 - Condition "!sd" is true. Returning: Size2()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5730 - Condition "!sd" is true. Returning: nullptr
  modules/text_server_adv/text_server_adv.cpp:5741 - Condition "!sd" is true. Returning: 0
  modules/text_server_adv/text_server_adv.cpp:5818 - Condition "!sd" is true. Returning: 0.0
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5803 - Condition "!sd" is true. Returning: Size2()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5730 - Condition "!sd" is true. Returning: nullptr
  modules/text_server_adv/text_server_adv.cpp:5741 - Condition "!sd" is true. Returning: 0
  modules/text_server_adv/text_server_adv.cpp:5818 - Condition "!sd" is true. Returning: 0.0
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5803 - Condition "!sd" is true. Returning: Size2()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5730 - Condition "!sd" is true. Returning: nullptr
  modules/text_server_adv/text_server_adv.cpp:5741 - Condition "!sd" is true. Returning: 0
  modules/text_server_adv/text_server_adv.cpp:5818 - Condition "!sd" is true. Returning: 0.0
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5803 - Condition "!sd" is true. Returning: Size2()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5730 - Condition "!sd" is true. Returning: nullptr
  modules/text_server_adv/text_server_adv.cpp:5741 - Condition "!sd" is true. Returning: 0
  modules/text_server_adv/text_server_adv.cpp:5818 - Condition "!sd" is true. Returning: 0.0
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5803 - Condition "!sd" is true. Returning: Size2()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5730 - Condition "!sd" is true. Returning: nullptr
  modules/text_server_adv/text_server_adv.cpp:5741 - Condition "!sd" is true. Returning: 0
  modules/text_server_adv/text_server_adv.cpp:5818 - Condition "!sd" is true. Returning: 0.0
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5770 - Condition "!sd" is true. Returning: Vector2i()
  modules/text_server_adv/text_server_adv.cpp:5803 - Condition "!sd" is true. Returning: Size2()

### Steps to reproduce

Add a text file and paste in an emoji into the text resource file then open it in the editor.

### Minimal reproduction project

[FileIOGuide.zip](https://github.com/godotengine/godot/files/10477742/FileIOGuide.zip)

ShapedTextDataAdvanced *new_sd = memnew(ShapedTextDataAdvanced);
	new_sd->parent = p_shaped;
	new_sd->start = p_start;
	new_sd->end = p_start + p_length;
	new_sd->orientation = sd->orientation;
	new_sd->direction = sd->direction;
	new_sd->custom_punct = sd->custom_punct;
	new_sd->para_direction = sd->para_direction;
	for (int i = 0; i < TextServer::SPACING_MAX; i++) {
		new_sd->extra_spacing[i] = sd->extra_spacing[i];
	}
	if (!_shape_substr(new_sd, sd, p_start, p_length)) {
		memdelete(new_sd);
		return RID();
	}
	return shaped_owner.make_rid(new_sd);
}
bool TextServerAdvanced::_shape_substr(ShapedTextDataAdvanced *p_new_sd, const ShapedTextDataAdvanced *p_sd, int64_t p_start, int64_t p_length) const {
	if (p_new_sd->valid) {
		return true;
	}
	p_new_sd->hb_buffer = hb_buffer_create();
	p_new_sd->line_breaks_valid = p_sd->line_breaks_valid;
	p_new_sd->justification_ops_valid = p_sd->justification_ops_valid;
	p_new_sd->sort_valid = false;
	p_new_sd->upos = p_sd->upos;
	p_new_sd->uthk = p_sd->uthk;
	if (p_length > 0) {
		p_new_sd->text = p_sd->text.substr(p_start - p_sd->start, p_length);
		p_new_sd->utf16 = p_new_sd->text.utf16();