### 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)

FontAdvanced *fd = font_owner.get_or_null(p_font_rid);
	ERR_FAIL_COND(!fd);
	ERR_FAIL_COND(p_image.is_null());
	MutexLock lock(fd->mutex);
	Vector2i size = _get_size_outline(fd, p_size);
	ERR_FAIL_COND(!_ensure_cache_for_size(fd, size));
	ERR_FAIL_COND(p_texture_index < 0);
	if (p_texture_index >= fd->cache[size]->textures.size()) {
		fd->cache[size]->textures.resize(p_texture_index + 1);
	}
	ShelfPackTexture &tex = fd->cache[size]->textures.write[p_texture_index];
	tex.imgdata = p_image->get_data();
	tex.texture_w = p_image->get_width();
	tex.texture_h = p_image->get_height();
	tex.format = p_image->get_format();
	Ref<Image> img = Image::create_from_data(tex.texture_w, tex.texture_h, false, tex.format, tex.imgdata);
	if (fd->mipmaps) {
		img->generate_mipmaps();
	}
	tex.texture = ImageTexture::create_from_image(img);
	tex.dirty = false;
}
Ref<Image> TextServerAdvanced::_font_get_texture_image(const RID &p_font_rid, const Vector2i &p_size, int64_t p_texture_index) const {