title: Check <head> contains specific <link> without JQuery
body: <p>Is it possible to check that the <code>&lt;head&gt;</code> contains a specific <code>&lt;link&gt;</code> tag?</p>
  
  <p>For example I would add a link to the head:</p>
  
  <pre><code>let link = document.createElement('link');
  link.href = 'https://my.path.css';
  link.type = 'text/css';
  link.rel = 'stylesheet';
  document.head.append(link);
  </code></pre>
  
  <p>Is it then possible to check that it is present within the head?</p>
  
  <p>I know that I can get an HTMLCollection with</p>
  
  <pre><code>const headChildren = document.getElementsByTagName('head')[0].children;
  </code></pre>
  
  <p>But I can't seem to navigate this to check...</p>