Fixed typo in the service declaration

Author: benatespina

src/BenGorFile/FileBundle/Controller/Api/GetFilesController.php

@@ -33,7 +33,7 @@ public function byIdsAction(Request $request, $fileClass)
 
         return new JsonResponse(
             $this->get(
-                'bengor.file.application.query.list_' . $fileClass . 'files_of_ids'
+                'bengor.file.application.query.list_' . $fileClass . 's_of_ids'
             )->__invoke(new ListFilesOfIdsQuery($ids))
         );
     }