magento-test/app/code/Magento/Tax/etc/events.xml

<?xml version="1.0"?>
<!--
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */
-->
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Event/etc/events.xsd">
    <event name="catalog_product_view_config">
        <observer name="tax" instance="\Magento\Tax\Observer\UpdateProductOptionsObserver" />
    </event>
    <event name="catalog_product_option_price_configuration_after">
        <observer name="tax" instance="Magento\Tax\Observer\GetPriceConfigurationObserver"/>
    </event>
</config>