### 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.
List<Node *> nodes_owned_by_original_node;
				original_node->get_owned_by(original_node, &nodes_owned_by_original_node);
				for (Node *owned_node : nodes_owned_by_original_node) {
					owned_node->set_owner(nullptr);
				}
				
				while (original_node->get_child_count()) {
					Node *child = original_node->get_child(0);
					original_node->remove_child(child);
					child->queue_free();
				}
				
				bool is_editable = true;
				Node *owner = original_node->get_owner();
				if (owner) {
					is_editable = owner->is_editable_instance(original_node);
				}
				
				Ref<PackedScene> current_packed_scene;
				if (original_node->get_scene_file_path() == p_instance_path) {
					
					
					current_packed_scene = instance_scene_packed_scene;
				} else {
					
					
					List<String> required_load_paths;
					String scene_path = original_node->get_scene_file_path();