title: "async" is not a member of a group specified for any attribute
body: <p>Running my site through the W3C validator (and in other validators), I'm getting the following errors with my Google Ads:</p>
  
  <blockquote>
    <ul>
    <li><code>async</code> is not a member of a group specified for any attribute</li>
    <li>there is no attribute <code>data-ad-client</code></li>
    <li>there is no attribute <code>data-ad-slot</code></li>
    </ul>
  </blockquote>
  
  <p>Is there anyway to correct these? I'd love to see the site pass 100%.</p>