Remove importing Controller from two examples in validation.md (#9073)

Author: azim-kordpour

validation.md

@@ -69,7 +69,6 @@ Next, let's take a look at a simple controller that handles incoming requests to
 
     namespace App\Http\Controllers;
 
-    use App\Http\Controllers\Controller;
     use Illuminate\Http\RedirectResponse;
     use Illuminate\Http\Request;
     use Illuminate\View\View;
@@ -543,7 +542,6 @@ If you do not want to use the `validate` method on the request, you may create a
 
     namespace App\Http\Controllers;
 
-    use App\Http\Controllers\Controller;
     use Illuminate\Http\RedirectResponse;
     use Illuminate\Http\Request;
     use Illuminate\Support\Facades\Validator;