Use local time helper to format the time

Also avoids JS error we were creating.

app/views/events/_day.html.erb

@@ -1,4 +1,4 @@
-<div class="events--day" data-controller="related-element" 
+<div class="events--day" data-controller="related-element"
      data-related-element-highlight-class="event--related">
   <% if events.any? %>
     <h2 class="txt-x-large margin-block-end"><%= event_day_title(activity_day) %></h2>
@@ -10,10 +10,7 @@
       <% events.each do | hour_column, cluster| %>
         <%= event_cluster_tag(*hour_column) do %>
           <%= render cluster %>
-
-          <time class="event__timestamp txt-small translucent" data-local-time-target="time" datetime="<%= cluster.first.created_at.strftime("%H:%M") %>">
-            <%= cluster.first.created_at.strftime("%l:%M %P").strip %>
-          </time>
+          <%= local_datetime_tag cluster.first.created_at, class: "event__timestamp txt-small translucent" %>
         <% end %>
       <% end %>
     </div>