Merge pull request #385 from remco-schouten/patch-1

Update RefundDataBuilder.php

Gateway/Request/RefundDataBuilder.php

@@ -191,7 +191,7 @@ class RefundDataBuilder implements BuilderInterface
 
         foreach ($creditMemo->getAllItems() as $refundItem) {
             ++$count;
-            $numberOfItems = $refundItem->getQty();
+            $numberOfItems = (int)$refundItem->getQty();
 
             $formFields = $this->adyenHelper->createOpenInvoiceLineItem(
                 $formFields,