newsupernova/vendor/magento/module-tax/view/adminhtml/templates/toolbar/rate/save.phtml

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

// @codingStandardsIgnoreFile

?>
<?php if ($form): ?>
<?= $form->toHtml() ?>

<script>
require([
    "jquery",
    "mage/mage"
], function($){

    $('#<?= /* @escapeNotVerified */ $form->getForm()->getId() ?>').mage('form').mage('validation');

    $(document).ready(function () {
        'use strict';

        $('.field-zip_from').addClass('ignore-validate');
        $('.field-zip_to').addClass('ignore-validate');

        $('#zip_is_range').on('change.zipRange', function(){

            var elem = $(this),
                zipFrom =$('.field-zip_from'),
                zipTo =$('.field-zip_to'),
                zipCode =$('.field-tax_postcode');

            if (elem.is(':checked')) {
                zipCode.addClass('hidden').addClass('ignore-validate');
                zipFrom.removeClass('hidden').removeClass('ignore-validate');
                zipTo.removeClass('hidden').removeClass('ignore-validate');

            } else {
                zipCode.removeClass('hidden').removeClass('ignore-validate');
                zipFrom.addClass('hidden').addClass('ignore-validate');
                zipTo.addClass('hidden').addClass('ignore-validate');
            }

        });
    });

});
</script>
<?php endif; ?>