persistent.php

<?php
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */

require __DIR__ . '/../../../Magento/Customer/_files/customer.php';
require __DIR__ . '/../../../Magento/Customer/_files/customer_address.php';

/** @var \Magento\Persistent\Model\Session $persistentSession */
$persistentSession = \Magento\TestFramework\Helper\Bootstrap::getObjectManager()->get(
    \Magento\Persistent\Model\Session::class
);
$persistentSession->setCustomerId($customer->getId())->save();