Derby: remove count from clear completed button

examples/derby/views/todos/index.html

@@ -54,7 +54,7 @@
 			</li>
 		</ul>
 		<button x-bind=click:clearCompleted id="clear-completed" class="{#unless _list.completed}non-completed{/}">
-			Clear completed (<span>{_list.completed.length}</span>)
+			Clear completed
 		</button>
 	</footer>