Filter get_queue_member_list() if queue_id is passed

Otherwise, we'll list all members from all queues and not just the queue
specific members

Change-Id: I1c6be4086a32e43982bca308872cfa6015a64bbf
Signed-off-by: Paul Belanger <paul.belanger@polybeacon.com>
Refactor duplicate db unit test code into base

Change-Id: Ie8f6e72ebf3c37472291d326e04825d03c76265b
Signed-off-by: Paul Belanger <paul.belanger@polybeacon.com>