### 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.
Dictionary state;
	state["main_tab"] = _get_current_main_editor();
	state["scene_tree_offset"] = SceneTreeDock::get_singleton()->get_tree_editor()->get_scene_tree()->get_vscroll_bar()->get_value();
	state["property_edit_offset"] = InspectorDock::get_inspector_singleton()->get_scroll_offset();
	state["node_filter"] = SceneTreeDock::get_singleton()->get_filter();
	return state;
}
void EditorNode::_set_main_scene_state(Dictionary p_state, Node *p_for_scene) {
	if (get_edited_scene() != p_for_scene && p_for_scene != nullptr) {
		return; 
	}
	changing_scene = false;
	int current_tab = -1;
	for (int i = 0; i < editor_table.size(); i++) {
		if (editor_plugin_screen == editor_table[i]) {
			current_tab = i;
			break;
		}
	}
	if (p_state.has("editor_index")) {
		int index = p_state["editor_index"];
		if (current_tab < 2) { 
			if (index < 2 || !get_edited_scene()) {
				editor_select(index);