### Godot version

v4.0.beta.custom_build [fab9926a9]

### System information

Fedora 37

### Issue description

When creating a new inherited scene, saving the scene (for example with Ctrl+S) defaults to overwriting the scene being inherited, instead of prompting for a location to save to.

### Steps to reproduce

1. Create a new inherited scene
2. Press Ctrl+S

If the scene being inherited is imported (for example from a glTF), an error displays. If the inherited scene is a .tscn or .scn, it gets overridden by an inherited scene that tries to inherit itself, which is impossible and thus corrupt.

### Minimal reproduction project

N/A
}
			} else if (extensions.size()) {
				String root_name = scene->get_name();
				root_name = EditorNode::adjust_scene_name_casing(root_name);
				file->set_current_path(root_name + "." + extensions.front()->get().to_lower());
			}
			file->popup_file_dialog();
			file->set_title(TTR("Save Scene As..."));
		} break;
		case FILE_SAVE_ALL_SCENES: {
			_save_all_scenes();
		} break;
		case FILE_EXPORT_PROJECT: {
			project_export->popup_export();
		} break;
		case FILE_EXTERNAL_OPEN_SCENE: {
			if (unsaved_cache && !p_confirmed) {
				confirmation->set_ok_button_text(TTR("Open"));
				confirmation->set_text(TTR("Current scene not saved. Open anyway?"));
				confirmation->popup_centered();
				break;
			}
			bool oprev = opening_prev;
			Error err = load_scene(external_file);
			if (err == OK && oprev) {
				previous_scenes.pop_back();
				opening_prev = false;
			}
		} break;
		case EDIT_UNDO: {