[11.x] signature typo (#50766)

* typo

* Update HasMiddleware.php

---------

Co-authored-by: Taylor Otwell <[email protected]>

Author: abrahamgreyson

src/Illuminate/Routing/Controllers/HasMiddleware.php

@@ -7,7 +7,7 @@ interface HasMiddleware
     /**
      * Get the middleware that should be assigned to the controller.
      *
-     * @return \Illuminate\Routing\Controllers\Middleware|array
+     * @return \Illuminate\Routing\Controllers\Middleware[]
      */
     public static function middleware();
 }