magento-test/app/code/Magento/Sales/Test/Mftf/Data/CreditMemoData.xml

<?xml version="1.0" encoding="UTF-8"?>

<!--
 /**
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
-->

<entities xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:noNamespaceSchemaLocation="urn:magento:mftf:DataGenerator/etc/dataProfileSchema.xsd">

    <entity name="CreditMemo" type="CreditMemo">
       <var key="quote_id" entityKey="return" entityType="CustomerCart"/>
    </entity>

</entities>