ACP2E-2246: [Cloud] Multiple RMAs for a single product can be created via REST API

- fixtures couldn't be processed anymore because of built-in model validations

Author: aplapana

dev/tests/integration/testsuite/Magento/Sales/_files/order_fixture_store.php

@@ -41,6 +41,7 @@
 /** @var OrderItem $orderItem */
 $orderItem = $objectManager->create(OrderItem::class);
 $orderItem->setProductId($product->getId())->setQtyOrdered(2);
+$orderItem->setProductType(\Magento\Catalog\Model\Product\Type::TYPE_SIMPLE);
 
 /** @var Order $order */
 $order = $objectManager->create(Order::class);