Resolve #3505245 "Drupal 11 support"

Closes #3505245

assets/css/ai-auto-reference.css

 .fieldset__ai-auto-reference,
-.fieldset__ai-auto-reference:not(.fieldgroup) {
+.fieldset__ai-auto-reference:not(.fieldgroup),
+.fieldset.fieldset__ai-auto-reference,
+.fieldset.fieldset__ai-auto-reference:not(.fieldgroup) {
   /** Prevent Gin theme compatibility issue for the apply form */
   background-color: white;
 }