### 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)

case EDIT_TO_LOWERCASE: {
			_convert_case(CodeTextEditor::LOWER);
		} break;
		case EDIT_CAPITALIZE: {
			_convert_case(CodeTextEditor::CAPITALIZE);
		} break;
		case EDIT_EVALUATE: {
			Expression expression;
			tx->begin_complex_operation();
			for (int caret_idx = 0; caret_idx < tx->get_caret_count(); caret_idx++) {
				Vector<String> lines = tx->get_selected_text(caret_idx).split("\n");
				PackedStringArray results;
				for (int i = 0; i < lines.size(); i++) {
					String line = lines[i];
					String whitespace = line.substr(0, line.size() - line.strip_edges(true, false).size()); 
					if (expression.parse(line) == OK) {
						Variant result = expression.execute(Array(), Variant(), false, true);
						if (expression.get_error_text().is_empty()) {
							results.push_back(whitespace + result.get_construct_string());
						} else {
							results.push_back(line);
						}
					} else {
						results.push_back(line);
					}
				}
				tx->insert_text_at_caret(String("\n").join(results), caret_idx);
			}
			tx->end_complex_operation();
		} break;