Merge pull request #6394 from edx/aria-labelledby

Should be aria-labelledby

lms/templates/dashboard.html

@@ -376,7 +376,7 @@
 </section>
 
 <section id="unenroll-modal" class="modal unenroll-modal" aria-hidden="true">
-  <div class="inner-wrapper" role="alertdialog" aria-labelledy="unenrollment-modal-title">
+  <div class="inner-wrapper" role="dialog" aria-labelledby="unenrollment-modal-title">
     <button class="close-modal">
       <i class="icon-remove"></i>
       <span class="sr">