### 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
case FILE_SAVE_AND_RUN_MAIN_SCENE: {
			ProjectSettings::get_singleton()->set("application/run/main_scene", p_file);
			ProjectSettings::get_singleton()->save();
			if (file->get_file_mode() == EditorFileDialog::FILE_MODE_SAVE_FILE) {
				_save_default_environment();
				_save_scene_with_preview(p_file);
				if ((bool)pick_main_scene->get_meta("from_native", false)) {
					run_native->resume_run_native();
				} else {
					_run(false, p_file);
				}
			}
		} break;
		case FILE_EXPORT_MESH_LIBRARY: {
			Ref<MeshLibrary> ml;
			if (file_export_lib_merge->is_pressed() && FileAccess::exists(p_file)) {
				ml = ResourceLoader::load(p_file, "MeshLibrary");
				if (ml.is_null()) {
					show_accept(TTR("Can't load MeshLibrary for merging!"), TTR("OK"));
					return;
				}
			}
			if (ml.is_null()) {
				ml = Ref<MeshLibrary>(memnew(MeshLibrary));
			}
			MeshLibraryEditor::update_library_file(editor_data.get_edited_scene_root(), ml, true, file_export_lib_apply_xforms->is_pressed());
			Error err = ResourceSaver::save(ml, p_file);
			if (err) {
				show_accept(TTR("Error saving MeshLibrary!"), TTR("OK"));
				return;