### 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)

theme_cache.table_h_separation = get_theme_constant(SNAME("table_h_separation"));
	theme_cache.table_v_separation = get_theme_constant(SNAME("table_v_separation"));
	theme_cache.table_odd_row_bg = get_theme_color(SNAME("table_odd_row_bg"));
	theme_cache.table_even_row_bg = get_theme_color(SNAME("table_even_row_bg"));
	theme_cache.table_border = get_theme_color(SNAME("table_border"));
	theme_cache.base_scale = get_theme_default_base_scale();
}
void RichTextLabel::_notification(int p_what) {
	switch (p_what) {
		case NOTIFICATION_MOUSE_EXIT: {
			if (meta_hovering) {
				meta_hovering = nullptr;
				emit_signal(SNAME("meta_hover_ended"), current_meta);
				current_meta = false;
				queue_redraw();
			}
		} break;
		case NOTIFICATION_RESIZED: {
			_stop_thread();
			main->first_resized_line.store(0); 
			queue_redraw();
		} break;
		case NOTIFICATION_THEME_CHANGED: {
			_stop_thread();
			main->first_invalid_font_line.store(0); 
			queue_redraw();
		} break;
		case NOTIFICATION_ENTER_TREE: {
			_stop_thread();
			if (!text.is_empty()) {