title: Google Analytics get tracker by trackingId
body: <p>I currently have this code, to try and find the right tracker I need (among 8-12 trackers):</p>
  
  <pre><code>ga.getAll().forEach(function(tracker) {
      if(tracker.get('trackingId') === "UA-62921111-4") {
  </code></pre>
  
  <p>Instead of getting every tracker and iterating through them, is there an easy way to do something like <code>ga.getTracker("UA-62921111-4")</code>?</p>