Format timestamp according to RFC 3339 with moment.js
<p>Like this:</p>

<pre><code>const RFC_3339 = 'YYYY-MM-DDTHH:mm:ss';
moment.utc().format(RFC_3339);
</code></pre>

<p>I need the timestamp to have a 'Z' at the end. Is there a better way than just <code>+'Z'</code>?</p>

<p>It should match the python code on the backend: </p>

<pre><code>RFC_3339_FMT = "%Y-%m-%dT%H:%M:%SZ"
</code></pre>