### 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.
if (!scene_path.is_empty()) {
						required_load_paths.push_front(scene_path);
					}
					Ref<SceneState> inherited_state = original_node->get_scene_inherited_state();
					while (inherited_state.is_valid()) {
						String inherited_path = inherited_state->get_path();
						
						if (!inherited_path.is_empty()) {
							required_load_paths.push_front(inherited_path);
						}
						inherited_state = inherited_state->get_base_scene_state();
					}
					
					
					for (String path : required_load_paths) {
						if (!local_scene_cache.find(path)) {
							current_packed_scene = ResourceLoader::load(path, "", ResourceFormatLoader::CACHE_MODE_IGNORE, &err);
							current_packed_scene->set_path(path, true);
							local_scene_cache[path] = current_packed_scene;
						} else {
							current_packed_scene = local_scene_cache[path];
						}
					}
				}
				ERR_FAIL_COND(current_packed_scene.is_null());
				
				Node *instantiated_node = nullptr;
				if (current_packed_scene.is_valid()) {
					instantiated_node = current_packed_scene->instantiate(PackedScene::GEN_EDIT_STATE_INSTANCE);
				}