### 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.
editable_info = TTR("This resource belongs to a scene that was instantiated or inherited.\nChanges to it must be made inside the original scene.");
					}
				}
			} else {
				if (FileAccess::exists(base_path + ".import")) {
					editable_info = TTR("This resource belongs to a scene that was imported, so it's not editable.\nPlease read the documentation relevant to importing scenes to better understand this workflow.");
				}
			}
		} else if (current_res->get_path().is_resource_file()) {
			if (FileAccess::exists(current_res->get_path() + ".import")) {
				editable_info = TTR("This resource was imported, so it's not editable. Change its settings in the import panel and then re-import.");
			}
		}
	} else if (is_node) {
		Node *current_node = Object::cast_to<Node>(current_obj);
		ERR_FAIL_COND(!current_node);
		InspectorDock::get_inspector_singleton()->edit(current_node);
		if (current_node->is_inside_tree()) {
			NodeDock::get_singleton()->set_node(current_node);
			SceneTreeDock::get_singleton()->set_selected(current_node);
			InspectorDock::get_singleton()->update(current_node);
			if (!inspector_only && !skip_main_plugin) {
				skip_main_plugin = stay_in_script_editor_on_node_selected && ScriptEditor::get_singleton()->is_visible_in_tree();
			}
		} else {
			NodeDock::get_singleton()->set_node(nullptr);
			SceneTreeDock::get_singleton()->set_selected(nullptr);
			InspectorDock::get_singleton()->update(nullptr);
		}
		if (get_edited_scene() && !get_edited_scene()->get_scene_file_path().is_empty()) {