### Godot version

v4.0.beta10.official [d0398f62f]

### System information

Windows 22H2, Compatibility, GeForce GTX 550 Ti

### Issue description

Multiple lines of error messages are copied without line breaks:
The script editor's error panel shows:
```
Line 6:Expected parameter name.
Line 6:Expected closing ")" after function parameters.
Line 6:Expected ":" after function declaration.
```
But selecting and copying them `ctrl c`, copies them without line breaks:
```
Line 6:Expected parameter name.Line 6:Expected closing ")" after function parameters.Line 6:Expected ":" after function declaration.
```


### Steps to reproduce

- start Godot
- open the attached project
- open the script `Node2D.gd`
The status bar shows an error message.
- click on the red circle with an x in it, and the number 3 to the right of the circle.
The script editor's error panel shows three messages:
>Line 6:Expected parameter name.
Line 6:Expected closing ")" after function parameters.
Line 6:Expected ":" after function declaration.

- select all three lines, and copy them `ctrl c`
- in the script editor, click on the empty line 12 to place the cursor there.
- paste `ctrl v`

### Expected
The copied lines should be pasted on three lines, as they appeared in the error panel.

### Observed
There are no line breaks, they appear on the same line:
```
Line 6:Expected parameter name.Line 6:Expected closing ")" after function parameters.Line 6:Expected ":" after function declaration.
```


### Minimal reproduction project

[issue, error messages copied without line breaks.zip](https://github.com/godotengine/godot/files/10361376/issue.error.messages.copied.without.line.breaks.zip)

if (!bool(EDITOR_GET("text_editor/external/use_external_editor"))) {
		return;
	}
	ERR_FAIL_COND(!get_tree());
	HashSet<Ref<Script>> scripts;
	Node *base = get_tree()->get_edited_scene_root();
	if (base) {
		_find_changed_scripts_for_external_editor(base, base, scripts);
	}
	for (const Ref<Script> &E : scripts) {
		Ref<Script> scr = E;
		if (p_for_script.is_valid() && p_for_script != scr) {
			continue;
		}
		if (scr->is_built_in()) {
			continue; 
		}
		uint64_t last_date = scr->get_last_modified_time();
		uint64_t date = FileAccess::get_modified_time(scr->get_path());
		if (last_date != date) {
			Ref<Script> rel_scr = ResourceLoader::load(scr->get_path(), scr->get_class(), ResourceFormatLoader::CACHE_MODE_IGNORE);
			ERR_CONTINUE(!rel_scr.is_valid());
			scr->set_source_code(rel_scr->get_source_code());
			scr->set_last_modified_time(rel_scr->get_last_modified_time());
			scr->update_exports();
			_trigger_live_script_reload();
		}
	}
}
void ScriptTextEditor::_code_complete_scripts(void *p_ud, const String &p_code, List<ScriptLanguage::CodeCompletionOption> *r_options, bool &r_force) {