Add policy check to calendar create button

Author: rsmithlal

app/views/better_together/calendars/index.html.erb

@@ -1,9 +1,11 @@
 <div class="container mt-5">
   <h1 class="mb-4 text-center"><i class="fas fa-calendar-alt"></i> Calendars</h1>
 
-  <div class="text-center my-4">
-    <%= link_to "New calendar", new_calendar_path, class: "btn btn-success" %>
-  </div>
+  <% if policy(resource_class).create? %>
+    <div class="text-center my-4">
+      <%= link_to "New calendar", new_calendar_path, class: "btn btn-success" %>
+    </div>
+  <% end %>
 
   <div id="better_together_calendars" class="row row-cols-1 row-cols-md-2 g-4">
     <%= render @calendars %>