Not working — adding Bugherd to Enfold Child via functions.php

I have added to the Enfold Child for http://pro-grahamstory.sgdev.io the following code but it is not being inserted into the headed. All plugins disabled. Thoughts?

// ———-
// Add javascript function to enable Bugherd
// ———-

add_action(‘wp_head’, ‘add_bugherd’);
function add_bugherd(){
?>
<script type=”text/javascript” src=”https://www.bugherd.com/sidebarv2.js?apikey=DELETED&#8221; async=”true”></script>
<?php
};