### Godot version

4.1.beta (7b1387ff2)

### System information

Mageia 9, Linux

### Issue description

When opening an empty project in latest `master`, I get these errors:
```
ERROR: Index p_idx = -1 is out of bounds (edited_scene.size() = 1).
   at: get_scene_path (editor/scu/../editor_data.cpp:880)
ERROR: Index p_idx = -1 is out of bounds (edited_scene.size() = 1).
   at: check_and_update_scene (editor/scu/../editor_data.cpp:683)
ERROR: Index p_idx = -1 is out of bounds (edited_scene.size() = 1).
   at: set_edited_scene (editor/scu/../editor_data.cpp:745)
```

Possibly related to recent changes to restore past sessions, but there's nothing to restore in this case?

### Steps to reproduce

- Create a new project, edit it
- Quit to project manager
- Re-open the newly created project -> errors

### Minimal reproduction project

Empty project.
}
			_proceed_closing_scene_tabs();
		} break;
		case FILE_QUIT: {
			project_run_bar->stop_playing();
			_exit_editor(EXIT_SUCCESS);
		} break;
		case RUN_PROJECT_MANAGER: {
			project_run_bar->stop_playing();
			_exit_editor(EXIT_SUCCESS);
			String exec = OS::get_singleton()->get_executable_path();
			List<String> args;
			for (const String &a : Main::get_forwardable_cli_arguments(Main::CLI_SCOPE_TOOL)) {
				args.push_back(a);
			}
			String exec_base_dir = exec.get_base_dir();
			if (!exec_base_dir.is_empty()) {
				args.push_back("--path");
				args.push_back(exec_base_dir);
			}
			args.push_back("--project-manager");
			Error err = OS::get_singleton()->create_instance(args);
			ERR_FAIL_COND(err);
		} break;
		case RELOAD_CURRENT_PROJECT: {
			restart_editor();
		} break;
	}
}
void EditorNode::_update_file_menu_opened() {