[front] better default for 'Last update' field

public/index.html

@@ -24,8 +24,9 @@
                     <h1 id="page-title">RobotLearn Cluster Monitor</h1>
                 </div>
                 <div class="container centered">
-                    <p id="last-updated"><span style="color:var(--orange-moche)">Last update:</span>
-                    12/31 23:59:59</p>
+                    <p id="last-updated">
+                        <span style="color:var(--orange-moche)">Last update:</span> 23:59:59
+                    </p>
                 </div>
             </div>
             <!-- <div class="container" id="page-selection"> -->