Use consistent markup for failed ports

This seems to be a leftover from the previous version of the GUI.

Author: smortex

src/share/poudriere/html/build.html

@@ -336,8 +336,10 @@
               </table>
             </div>
             <!-- #built -->
-            <div id="failed_div" class="status" style="display: none">
-              <h2 id="failed">Failed ports</h2>
+            <div id="failed_div" style="display: none">
+              <div class="card my-3 bg-dark text-white fs-5">
+                <div class="card-body fs-5">Failed Ports</div>
+              </div>
               <table class="table table-striped" id="failed_table">
                 <thead>
                   <tr>