title: Tag User group knowing only name with a bot on slack
body: <p>On slack - I can tag a user directly from my both with the following text syntax :</p>
  
  <pre><code>hello Francois &lt;@francois&gt;
  </code></pre>
  
  <p>I would like to do the same with a group (unfortunately my app only know the group name not the group ID). Is there a syntax to do so - the following syntax does not work :</p>
  
  <pre><code>hello group &lt;@group&gt;
  </code></pre>