Issue #2581407 by davidhernandez, LewisNyman, emma.maria, Saphyel: Remove the...

Issue #2581407 by davidhernandez, LewisNyman, emma.maria, Saphyel: Remove the obsoletely named Classy library attached to Bartik's comment.html.twig as Bartik uses its own styles.

core/themes/bartik/templates/comment.html.twig

@@ -64,9 +64,6 @@
  * @see template_preprocess_comment()
  */
 #}
-{% if threaded %}
-  {{ attach_library('classy/drupal.comment.threaded') }}
-{% endif %}
 {%
   set classes = [
     'comment',