### 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.
switch (p_what) {
		case NOTIFICATION_PROCESS: {
			if (opening_prev && !confirmation->is_visible()) {
				opening_prev = false;
			}
			bool global_unsaved = EditorUndoRedoManager::get_singleton()->is_history_unsaved(EditorUndoRedoManager::GLOBAL_HISTORY);
			bool scene_or_global_unsaved = global_unsaved || EditorUndoRedoManager::get_singleton()->is_history_unsaved(editor_data.get_current_edited_scene_history_id());
			if (unsaved_cache != scene_or_global_unsaved) {
				unsaved_cache = scene_or_global_unsaved;
				_update_title();
			}
			if (editor_data.is_scene_changed(-1)) {
				_update_scene_tabs();
			}
			
			uint64_t frame = Engine::get_singleton()->get_frames_drawn();
			uint64_t tick = OS::get_singleton()->get_ticks_msec();
			if (frame != update_spinner_step_frame && (tick - update_spinner_step_msec) > (1000 / 8)) {
				update_spinner_step++;