Fix spice/vnc console api samples tests

Start the consoleauth service, otherwise authorize_console() will fail
if we start timing out call()s in the fake RPC driver when there are no
consumers for a topic.

blueprint: oslo-messaging
Change-Id: Ieee37a0370c0b548c589a0573e6e8a68e10a6fdc
Merge "Fix spice/vnc console api samples tests"