title: Angular Ag-Grid, how to place a material progress spinner inside of the overlayNoRowsTemplate?
body: <p>I am trying to place a mat-progress-spinner inside of my agGrid when there are no rows to show. </p>
  
  <p>Something like this works:</p>
  
  <pre><code>private overlayNoRowsTemplate = '&lt;p&gt;No rows to show.&lt;/p&gt;';
  </code></pre>
  
  <p>But when I try to add the mat-progress-spinner it doesn't show</p>
  
  <pre><code>private overlayNoRowsTemplate = '&lt;mat-progress-spinner style="margin:0 auto;" mode="indeterminate"&gt;&lt;/mat-progress-spinner&gt;'
  </code></pre>
  
  <p>Is what I am trying to do even possible?</p>