Update contest.html

Author: pxsit

cms/server/contest/templates/contest.html

@@ -187,7 +187,7 @@ <h3 id="countdown_box">
                                     {{ sidebar_task_scores[t_iter.id][2] }}
                                 </span>
                 {% else %}
-                                <span class="task_score_badge task_score undefined">{% trans %}N/A{% endtrans %}</span>
+                                <span class="task_score_badge task_score score_0">0 / 0</span>
                 {% endif %}
             {% endif %}
                             </li>