### 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 (!p_object) {
		InspectorDock::get_inspector_singleton()->edit(nullptr);
		NodeDock::get_singleton()->set_node(nullptr);
		SceneTreeDock::get_singleton()->set_selected(nullptr);
		InspectorDock::get_singleton()->update(nullptr);
		hide_unused_editors();
		return;
	}
	ObjectID id = p_object->get_instance_id();
	if (id != editor_history.get_current()) {
		if (p_inspector_only) {
			editor_history.add_object(id, String(), true);
		} else if (p_property.is_empty()) {
			editor_history.add_object(id);
		} else {
			editor_history.add_object(id, p_property);
		}
	}
	_edit_current();
}
void EditorNode::save_default_environment() {
	Ref<Environment> fallback = get_tree()->get_root()->get_world_3d()->get_fallback_environment();
	if (fallback.is_valid() && fallback->get_path().is_resource_file()) {
		HashMap<Ref<Resource>, bool> processed;
		_find_and_save_edited_subresources(fallback.ptr(), processed, 0);
		save_resource_in_path(fallback, fallback->get_path());
	}
}
void EditorNode::hide_unused_editors(const Object *p_editing_owner) {