Properly edit the instanced node in the inspector

(cherry picked from commit f5d51288b895df5495871586b33977ab76ac02b8)

editor/scene_tree_dock.cpp

@@ -235,6 +235,7 @@ void SceneTreeDock::_perform_instance_scenes(const Vector<String> &p_files, Node
 	}
 
 	editor_data->get_undo_redo().commit_action();
+	editor->push_item(instances[instances.size() - 1]);
 }
 
 void SceneTreeDock::_replace_with_branch_scene(const String &p_file, Node *base) {