### 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.
file_menu->set_item_disabled(file_menu->get_item_index(FILE_OPEN_PREV), previous_scenes.is_empty());
	_update_undo_redo_allowed();
}
void EditorNode::_update_file_menu_closed() {
	file_menu->set_item_disabled(file_menu->get_item_index(FILE_OPEN_PREV), false);
}
VBoxContainer *EditorNode::get_main_screen_control() {
	return main_screen_vbox;
}
void EditorNode::editor_select(int p_which) {
	static bool selecting = false;
	if (selecting || changing_scene) {
		return;
	}
	ERR_FAIL_INDEX(p_which, editor_table.size());
	if (!main_editor_buttons[p_which]->is_visible()) { 
		return;
	}
	selecting = true;
	for (int i = 0; i < main_editor_buttons.size(); i++) {
		main_editor_buttons[i]->set_pressed(i == p_which);
	}
	selecting = false;
	EditorPlugin *new_editor = editor_table[p_which];
	ERR_FAIL_COND(!new_editor);
	if (editor_plugin_screen == new_editor) {
		return;