title: How to upgrade to a new installed gitlab runner version?
body: <p>I try to update my single gitlab runner from 11.0 to 11.3.1
  and followed the instruction on the gitlab <a href="https://docs.gitlab.com/runner/install/linux-repository.html" rel="noreferrer" title="gitlab documentation">doc</a>.</p>
  
  <p><em>sudo apt-get install gitlab-runner</em> will confirm that I have the new version installed:</p>
  
  <blockquote>
    <p>gitlab-runner is already the newest version (11.3.1).</p>
  </blockquote>
  
  <p>The last updates like 10.* to 11.0 worked absolutely fine but this time
  the runner still stays on 11.0 (in -help and gitlab-ci web ui).</p>
  
  <p>A restart of the runner don't change anything so it looks like I miss a major step for the update some how.</p>
  
  <p>It would be great to find out what I'm doing wrong, thanks in advance. :-)</p>
  
  <p>OS: Ubuntu 18.04.1</p>
  
  <p><em>(I'm relatively new in the linux and gitlab world so it could be something obvious)</em></p>
  
  <p>Used update command:</p>
  
  <pre><code># For Debian/Ubuntu/Mint
  sudo apt-get update
  sudo apt-get install gitlab-runner
  </code></pre>