BUG#7632: Creditmemo for an order that contains only one configurable product is not generated correctly

Author: glo80326

app/code/Magento/Sales/Model/Order/Creditmemo.php

@@ -563,6 +563,11 @@ public function isLast()
     {
         $items = $this->getAllItems();
         foreach ($items as $item) {
+            $orderItem = $item->getOrderItem();
+            if ($orderItem->isDummy()) {
+                continue;
+            }
+
             if (!$item->isLast()) {
                 return false;
             }