Fix double lock/group buttons when starting editor with empty scene

editor/plugins/canvas_item_editor_plugin.cpp

@@ -4011,6 +4011,8 @@ void CanvasItemEditor::_project_settings_changed() {
 void CanvasItemEditor::_notification(int p_what) {
 	switch (p_what) {
 		case NOTIFICATION_READY: {
+			_update_lock_and_group_button();
+
 			EditorRunBar::get_singleton()->connect("play_pressed", callable_mp(this, &CanvasItemEditor::_update_override_camera_button).bind(true));
 			EditorRunBar::get_singleton()->connect("stop_pressed", callable_mp(this, &CanvasItemEditor::_update_override_camera_button).bind(false));
 			ProjectSettings::get_singleton()->connect("settings_changed", callable_mp(this, &CanvasItemEditor::_project_settings_changed));