### 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)

int limit = 0;
			for (int i = 0; i < sd->text.length(); i++) {
				if (is_whitespace(data[i])) {
					int ks = _generate_kashida_justification_opportunies(sd->text, limit, i) + sd->start;
					if (ks != -1) {
						sd->jstops[ks] = true;
					}
					limit = i + 1;
				}
			}
			int ks = _generate_kashida_justification_opportunies(sd->text, limit, sd->text.length()) + sd->start;
			if (ks != -1) {
				sd->jstops[ks] = true;
			}
		} else {
			int limit = 0;
			while (ubrk_next(bi) != UBRK_DONE) {
				if (ubrk_getRuleStatus(bi) != UBRK_WORD_NONE) {
					int i = _convert_pos(sd, ubrk_current(bi));
					sd->jstops[i + sd->start] = false;
					int ks = _generate_kashida_justification_opportunies(sd->text, limit, i);
					if (ks != -1) {
						sd->jstops[ks + sd->start] = true;
					}
					limit = i;
				}
			}
			ubrk_close(bi);
		}