remove returning Unit in the end of foreach example

Author: toy

_overviews/cheatsheets/index.md

@@ -477,8 +477,7 @@ println(upper.getOrElse(""))</code></pre></td>
       <pre class="highlight"><code>option match {
   case Some(x) =&gt; f(x)
   case None    =&gt; ()
-}
-()</code></pre></td>
+}</code></pre></td>
       <td>Apply a procedure on optional value. Returns <code>Unit</code>.</td>
     </tr>
     <tr>