title: Is it possible to throttle the main job and not the sub tasks
body: <p>Is it possible to use the throttle-concurrent-builds-plugin in a jenkins pipeline job in a way that the job itself is limited to 2 builds per node and the parallel tasks in the testphase are not?</p>
  
  <p>To make it clear a short example:</p>
  
  <pre><code>throttle(['myThrottleCategory']) {
  node('testnode') {
      try {
             stage 'checkout scm'
             ....
  
             def tasks [:]
             tasks[0] = {
                 stage 'parallel test module A'
                 ...
             }
             tasks[1] = ...
             parallel tasks
            }
         } 
      }
  </code></pre>
  
  <p>The main job is throttled to avoid deadlocks and increase the performance. The sub-tasks shouldn´t be throttled, so the job can use all available executors.</p>