### Godot version

v4.1.stable.official [970459615]

### System information

Godot v4.1.stable - Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce MX330 (NVIDIA; 30.0.15.1169) - 11th Gen Intel(R) Core(TM) i5-1135G7 @ 2.40GHz (8 Threads)

### Issue description

Calling `RichTextLabel`'s `select_all` method has no visual indicator, but it must have one. 

### Steps to reproduce

- Add `RichTextLabel` node
- Set `selection_enabled` value to be `true`
- Call `$RichTextLabel.select_all() `method in `_ready`

### Minimal reproduction project

[RichTextLabel_bug.zip](https://github.com/godotengine/godot/files/12098913/RichTextLabel_bug.zip)

current_line = p_search_previous ? ending_line - 1 : ending_line + 1;
	} else if (p_search_previous) {
		current_line = ending_line;
		ending_line = 0;
	}
	
	while (current_line != ending_line) {
		
		if (current_line < 0) {
			current_line = to_line - 1;
		} else if (current_line >= to_line) {
			current_line = 0;
		}
		if (_search_line(main, current_line, p_string, char_idx, p_search_previous)) {
			scroll_to_selection();
			queue_redraw();
			return true;
		}
		if (current_line != ending_line) {
			p_search_previous ? current_line-- : current_line++;
		}
	}
	if (p_from_selection && selection.active) {
		
		return _search_line(main, current_line, p_string, char_idx, p_search_previous);
	} else {
		return false;
	}
}
String RichTextLabel::_get_line_text(ItemFrame *p_frame, int p_line, Selection p_selection) const {