title: Jenkins pipeline with polling triggers multiple times
body: <p>I've created a number of script syntax Jenkinsfiles with this header:</p>
  
  <pre><code>properties([
      pipelineTriggers([
          pollSCM('H/5 * * * *')
      ])
  ])
  </code></pre>
  
  <p>They almost always trigger at least twice for every commit. Once within 5 minutes of the commit, and again at +5 minutes from the first build. The builds are shorter than 5 minutes long, meaning the second build triggers after the first build has completed. Jenkins log shows both triggers as being identical, as though the second build is not aware of the first build.</p>
  
  <p>I don't understand how this isn't a larger issue. It makes continuous deployment extremely dangerous. Am I missing something?</p>