### 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.
distraction_free->set_pressed(p_enter);
	if (p_enter) {
		if (docks_visible) {
			set_docks_visible(false);
		}
	} else {
		set_docks_visible(true);
	}
}
bool EditorNode::is_distraction_free_mode_enabled() const {
	return distraction_free->is_pressed();
}
void EditorNode::add_control_to_dock(DockSlot p_slot, Control *p_control) {
	ERR_FAIL_INDEX(p_slot, DOCK_SLOT_MAX);
	dock_slot[p_slot]->add_child(p_control);
	_update_dock_slots_visibility();
}
void EditorNode::remove_control_from_dock(Control *p_control) {