Fixed bug that Hyperf\Scout\Searchable don't import namespace of function config. (#6406)

Author: gokure

src/Searchable.php

@@ -21,6 +21,7 @@
 use Hyperf\ModelListener\Collector\ListenerCollector;
 use Hyperf\Scout\Engine\Engine;
 
+use function Hyperf\Config\config;
 use function Hyperf\Support\class_uses_recursive;
 use function Hyperf\Support\make;