title: How to write Pipeline to discard old builds?
body: <p>The groovy syntax generator is NOT working for sample step <code>properties: Set Job Properties</code>.  I've selected <code>Discard old builds</code> and then entered <code>10</code> in the <code>Max # of builds to keep</code> field and then <code>Generate Groovy</code> and nothing shows up.</p>
  
  <p>Jenkins version: 2.7</p>