Quota pallet benchmark

pallets/quota/src/benchmarking.rs

@@ -120,4 +120,7 @@ assert_has_event::<T>(Event::<T>::RefundFailed ( account ).into());
             Pallet::<T>::queue_refund(dummy_refund.clone())
         }
     }: { Pallet::<T>::process_refund_queue(Weight::MAX) }
+    verify {
+        assert_eq!(RefundQueue::<T>::get().len(), 0);
+    }
 }