### Godot version

master

### System information

Godot v4.2.beta (0ea75d77c) - Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 2070 (NVIDIA; 31.0.15.3598) - Intel(R) Core(TM) i7-10750H CPU @ 2.60GHz (12 Threads)

### Issue description

When any of the Import, Filesystem, Node, or History docks are floating, changing an editor feature crashes the engine.
Changing any setting or selecting a different profile triggers it.

This is because `EditorNode::_feature_profile_changed` assumes the docks are in a `TabContainer`, and if they are floating they aren't in one.


### Steps to reproduce

Make any of these docks floating: Import, Filesystem, Node, or History
Open Editor Features (Editor -> Manage Editor Features...)
Make a profile (if you have none) or change a setting on the existing profile

### Minimal reproduction project

n/a
for (int i = 0; i < p_node->get_child_count(); i++) {
		Node *child = p_node->get_child(i);
		if (child->get_scene_file_path() == p_filename) {
			return true;
		}
		if (_validate_scene_recursive(p_filename, child)) {
			return true;
		}
	}
	return false;
}
int EditorNode::_save_external_resources() {
	
	int flg = 0;
	if (EDITOR_GET("filesystem/on_save/compress_binary_resources")) {
		flg |= ResourceSaver::FLAG_COMPRESS;
	}
	flg |= ResourceSaver::FLAG_REPLACE_SUBRESOURCE_PATHS;
	HashSet<String> edited_resources;
	int saved = 0;
	List<Ref<Resource>> cached;
	ResourceCache::get_cached_resources(&cached);
	for (Ref<Resource> res : cached) {
		if (!res->is_edited()) {