wordpress-preseed/wp-content/plugins/updraftplus/templates/wp-admin/settings/exclude-settings-modal/exclude-panel-submit.php

<?php if (!defined('UPDRAFTPLUS_DIR')) die('No direct access allowed'); ?>
<br>
<input type="button" class="updraft-exclude-submit button-primary" value="<?php _e('Add an exclusion rule', 'updraftplus');?>" data-panel="<?php echo esc_attr($panel);?>"/>