### Godot version

v4.2.dev4.official [549fcce5f]

### System information

Ubuntu 20.04 LTS

### Issue description

See title.

### Steps to reproduce

1. Create a new project
2. Create a csv file that includes the following
```
key,ar
key,placeholder
```
3. Add the generated `.translation` file to Project -> Project Settings... -> Localization
4. In Project -> Project Settings... -> Internationalization -> Locale, set `Test` to `ar`
5. Add a `LineEdit` node and type `-=[]{}`
6. Run the project, and notice that the text is on the right side, but the symbols are incorrectly in LTR (`-=[]{}`).  Correct output is `{}[]=-`
7. Back in the editor, add a single Arabic letter (any will do), and notice that `LineEdit` immediately (and correctly) flips the symbols, and the newly-added Arabic letter, to RTL.

**Notes**
- Identical behavior is seen with `TextEdit`.
- The purpose of steps 2-4 are to simulate an Arabic environment when the project is run, despite `OS.get_locale() == "en"` (or your system's current language).

### Minimal reproduction project

[rtlsymbols.zip](https://github.com/godotengine/godot/files/12525509/rtlsymbols.zip)
}
					_font_set_antialiasing(sysf.rid, key.antialiasing);
					_font_set_generate_mipmaps(sysf.rid, key.mipmaps);
					_font_set_multichannel_signed_distance_field(sysf.rid, key.msdf);
					_font_set_msdf_pixel_range(sysf.rid, key.msdf_range);
					_font_set_msdf_size(sysf.rid, key.msdf_source_size);
					_font_set_fixed_size(sysf.rid, key.fixed_size);
					_font_set_force_autohinter(sysf.rid, key.force_autohinter);
					_font_set_hinting(sysf.rid, key.hinting);
					_font_set_subpixel_positioning(sysf.rid, key.subpixel_positioning);
					_font_set_variation_coordinates(sysf.rid, var);
					_font_set_oversampling(sysf.rid, key.oversampling);
					_font_set_embolden(sysf.rid, key.embolden);
					_font_set_transform(sysf.rid, key.transform);
					_font_set_spacing(sysf.rid, SPACING_TOP, key.extra_spacing[SPACING_TOP]);
					_font_set_spacing(sysf.rid, SPACING_BOTTOM, key.extra_spacing[SPACING_BOTTOM]);
					_font_set_spacing(sysf.rid, SPACING_SPACE, key.extra_spacing[SPACING_SPACE]);
					_font_set_spacing(sysf.rid, SPACING_GLYPH, key.extra_spacing[SPACING_GLYPH]);
					if (system_fonts.has(key)) {
						system_fonts[key].var.push_back(sysf);
					} else {
						SystemFontCache &sysf_cache = system_fonts[key];
						sysf_cache.max_var = _font_get_face_count(sysf.rid);
						sysf_cache.var.push_back(sysf);
					}
					f = sysf.rid;
				}
				
			}
		}