Issue #3481158 by nchase: Neither timeline nor month view is showing up in node - fix last $.once

Closes #3481158

modules/bat_calendar_reference/js/bat_calendar_reference.js

@@ -10,7 +10,7 @@
         dow: [0, 1, 2, 3, 4, 5, 6],
       };
 
-      $('.cal').once().each(function () {
+      $(once('init-fullcalendar', '.cal', context)).each(function () {
         var lastSource;
         var cal_id = $(this).attr('id');