FEATURE: Show change name of user in staff logs (#6647)

https://meta.discourse.org/t/admins-changing-users-name-not-username-should-be-logged/99511

app/models/user_history.rb

@@ -144,7 +144,8 @@ class UserHistory < ActiveRecord::Base
       :delete_badge,
       :post_rejected,
       :merge_user,
-      :entity_export
+      :entity_export,
+      :change_name
     ]
   end