### Godot version

v4.0.beta.custom_build [fab9926a9]

### System information

Fedora 37

### Issue description

When creating a new inherited scene, saving the scene (for example with Ctrl+S) defaults to overwriting the scene being inherited, instead of prompting for a location to save to.

### Steps to reproduce

1. Create a new inherited scene
2. Press Ctrl+S

If the scene being inherited is imported (for example from a glTF), an error displays. If the inherited scene is a .tscn or .scn, it gets overridden by an inherited scene that tries to inherit itself, which is impossible and thus corrupt.

### Minimal reproduction project

N/A
while (valid_node_owner) {
		if (valid_node_owner == p_root) {
			break;
		}
		valid_node_owner = valid_node_owner->get_owner();
	}
	if ((valid_node_owner == p_root && (p_root != p_edited_scene || !p_edited_scene->get_scene_file_path().is_empty())) || node_part_of_subscene || p_node == p_root) {
		HashMap<StringName, Variant> modified_properties = get_modified_properties_for_node(p_node);
		
		List<Connection> connections_to;
		p_node->get_all_signal_connections(&connections_to);
		List<ConnectionWithNodePath> valid_connections_to;
		for (const Connection &c : connections_to) {
			Node *connection_target_node = Object::cast_to<Node>(c.callable.get_object());
			if (connection_target_node) {
				
				if (!c.callable.is_custom()) {
					ConnectionWithNodePath connection_to;
					connection_to.connection = c;
					connection_to.node_path = p_node->get_path_to(connection_target_node);
					valid_connections_to.push_back(connection_to);
				}
			}
		}
		
		List<Connection> connections_from;
		p_node->get_signals_connected_to_this(&connections_from);
		List<Connection> valid_connections_from;
		for (const Connection &c : connections_from) {
			Node *source_node = Object::cast_to<Node>(c.signal.get_object());