title: XCode 8 error "Project ERROR: Xcode not set up properly", even though the license has been accepted
body: <p>I can no longer build Qt project after updating to Xcode 8 today. I get the following error despite having followed the instructions from <a href="https://stackoverflow.com/a/35098040/634821">this answer</a>. </p>
  
  <blockquote>
    <p>Project ERROR: Xcode not set up properly. You may need to confirm the
    license agreement by running /usr/bin/xcodebuild.</p>
  </blockquote>
  
  <p>How to fix it?</p>