title: How do I configure a Jenkins multi-branch pipeline to build as a submodule?
body: <p>I have a project <a href="https://github.com/mozilla/kuma" rel="nofollow noreferrer">kuma</a> organized with submodules:</p>
  
  <ul>
  <li><a href="https://github.com/mozilla/kuma" rel="nofollow noreferrer">kuma</a>
  
  <ul>
  <li>Jenkinsfile (configured to test kuma)</li>
  <li><a href="https://github.com/mozilla-l10n/mdn-l10n" rel="nofollow noreferrer">locales</a></li>
  <li><a href="https://github.com/mdn/kumascript" rel="nofollow noreferrer">kumascript</a>
  
  <ul>
  <li>Jenkinsfile (configured to test kumascript)</li>
  </ul></li>
  <li>A bunch of other files</li>
  </ul></li>
  </ul>
  
  <p>I'd like to configure a multi-branch pipeline in Jenkins that watches for branches on the kumascript repo, to:</p>
  
  <ol>
  <li>Check out the master branch of kuma</li>
  <li>Update the locales to the commit in the master branch (a regular <code>git submodule update --init</code>)</li>
  <li>Update the kumascript submodule to the branch to test</li>
  <li>Run the Jenkinsfile in the kumascript branch</li>
  </ol>
  
  <p>Is this possible? Is there a better way to do this?</p>