Server returning 503 dumps raw HTML to the terminal

[cmarqu]

Our instance of GitHub Enterprise Server was down for maintenance when I ran watchgha, and I got the following output:

Server error '503 Service Temporarily Unavailable' for url 'https://github.example.com/api/v3/repos/foo/bar/actions/runs?per_page=40&branch=feat%2Fquux'
For more information check: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/503
[raw HTML here including base64-encoded background and octocat images]

Of the HTML, the following elements might be interesting to show and could easily be stripped of their HTML tags even without a proper HTML renderer:

<title>GitHub Enterprise is currently down for maintenance</title>

    <div class="content">
      <h1>Down for maintenance</h1>
      <br />
      <p style="font-size: 30px;"> Your GitHub Enterprise administrators are performing scheduled maintenance. <br /> </p>
      <p>
        If you have any questions,
        
          please visit
          <a href="foo.example.com">Internal help desk</a>
        
      </p>
    </div>