### 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)

CodeEdit *te = code_editor->get_text_editor();
	String text = te->get_text();
	List<String> fnc;
	if (script->get_language()->validate(text, script->get_path(), &fnc)) {
		
		functions.clear();
		for (const String &E : fnc) {
			functions.push_back(E);
		}
	}
	return functions;
}
void ScriptTextEditor::apply_code() {
	if (script.is_null()) {
		return;
	}
	script->set_source_code(code_editor->get_text_editor()->get_text());
	script->update_exports();
	code_editor->get_text_editor()->get_syntax_highlighter()->update_cache();
}
Ref<Resource> ScriptTextEditor::get_edited_resource() const {