ui: remove incomplete uninvite key

packages/ui-default/templates/contest_detail.html

@@ -35,7 +35,7 @@
           <p>{{ _('The contest is a flexible time contest. You need to complete the contest within a specified time after you attended.') }}</p>
         </blockquote>
       {% endif %}
-      {% if tdoc.code and tdoc.uninvite %}
+      {% if tdoc.code %}
         <blockquote class="note">
           <p>{{ _('The contest is a invitational contest. However it allow users attend contest without the invitation code. Those users will not be ranked.') }}</p>
         </blockquote>