Ping hubs when following somebody, too

app/services/follow_service.rb

@@ -9,6 +9,7 @@ class FollowService < BaseService
 
     follow = source_account.follow!(target_account)
     send_interaction_service.(follow.stream_entry, target_account)
+    source_account.ping!(atom_user_stream_url(id: source_account.id), HUB_URL)
   end
 
   private