### 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)

ScriptTextEditor *ste = (ScriptTextEditor *)p_ud;
	ste->_code_complete_script(p_code, r_options, r_force);
}
void ScriptTextEditor::_code_complete_script(const String &p_code, List<ScriptLanguage::CodeCompletionOption> *r_options, bool &r_force) {
	if (color_panel->is_visible()) {
		return;
	}
	Node *base = get_tree()->get_edited_scene_root();
	if (base) {
		base = _find_node_for_script(base, base, script);
	}
	String hint;
	Error err = script->get_language()->complete_code(p_code, script->get_path(), base, r_options, r_force, hint);
	if (err == OK) {
		code_editor->get_text_editor()->set_code_hint(hint);
	}
}
void ScriptTextEditor::_update_breakpoint_list() {