title: Azure DevOps Using Taskgroup in YAML Build
body: <p>I've created a Task group to encapsulate some functionality.
  If I use a regular build, I can add the task group through the normal wizard.</p>
  
  <p>Unfortunately, I need to use the task group inside a YAML build. I can't view the YAML of the "old" build to view how this should gonna happen. </p>
  
  <p>The things I've tried:</p>
  
  <pre><code>  - task: TaskGroupName@1
      displayName: 'RunTests' 
      inputs:
        TestConfiguration: 'some.xml'
        TestCaseFilter: $(TestCaseFilter)
        UnitTestFolders: $(UnitTestFolders)
  </code></pre>