### 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)

int processed_glyphs = 0;
			while (ofs.y < size.height && from_line < to_line) {
				MutexLock lock(main->lines[from_line].text_buf->get_mutex());
				visible_paragraph_count++;
				visible_line_count += _draw_line(main, from_line, ofs, text_rect.size.x, theme_cache.default_color, theme_cache.outline_size, theme_cache.font_outline_color, theme_cache.font_shadow_color, theme_cache.shadow_outline_size, shadow_ofs, processed_glyphs);
				ofs.y += main->lines[from_line].text_buf->get_size().y + main->lines[from_line].text_buf->get_line_count() * theme_cache.line_separation;
				from_line++;
			}
		} break;
		case NOTIFICATION_INTERNAL_PROCESS: {
			if (is_visible_in_tree()) {
				if (!is_ready()) {
					return;
				}
				double dt = get_process_delta_time();
				_update_fx(main, dt);
				queue_redraw();
			}
		} break;
		case NOTIFICATION_FOCUS_EXIT: {
			if (deselect_on_focus_loss_enabled) {
				deselect();
			}
		} break;
		case NOTIFICATION_DRAG_END: {
			selection.drag_attempt = false;
		} break;
	}
}
Control::CursorShape RichTextLabel::get_cursor_shape(const Point2 &p_pos) const {