feat: Remove Flame Jam 2025 banner (#78)

Note: using comments to make it super easy to re-add later, since we
don't have a configuration / settings framework in place.

Author: luanpotter

_includes/callout.html

@@ -1,7 +1,9 @@
+{% comment %}
 <div class="main-border w-full">
     <div class="main-border-inner p-4">
         <p class="text-center">
             Our <a class="link" href="https://itch.io/jam/flame-jam-2025">Flame Game Jam 2025</a> is happening on 19-28th of April on itch.io! You do not want to miss it!
         </p>
     </div>
-</div>
+</div>
+{% endcomment %}