### 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 (EDITOR_3D < main_editor_buttons.size() && main_editor_buttons[EDITOR_3D]->is_visible()) {
		
		editor_select(EDITOR_3D);
		return;
	}
	
	
	for (int i = 0; i < main_editor_buttons.size(); i++) {
		Button *editor_button = main_editor_buttons[i];
		if (editor_button->is_visible()) {
			editor_select(i);
			return;
		}
	}
	editor_select(-1);
}
void EditorNode::_notification(int p_what) {