Cleanup listener after stopping rpc server

If you don't close the AMQP connection, then the connection
remains open and the next time when the messages are sent on
the listening topic, then some of the messages will not be processed
as there is no dispatcher running to process the message.

Closes-Bug: #1335086
Change-Id: I1f39eedf1500b6b6209ae0222f32e08e304895e0
Merge "Cleanup listener after stopping rpc server"