Message queue node should apply active filter at publish time not subscribe time

I'm not sure how big a difference this will make during operations, but the current implementation means that if a lot of messages were queued before the queue was set to inactive, all of them will be sent, and any new messages will be dropped.

I think a more intuitive behavior would be to have the queue continue accumulating/dropping messages based on its configuration (size, lifo/fifo), but have the get_next_message calls filter on whether a topic is in the list of active queues.