Fixes wrong Qpid protocol configuration

notify_qpid.py is suffering from the same issue as described in
launchpad bug https://bugs.launchpad.net/oslo/+bug/1158807.
Instead of setting connection.transport, it is attempting to
set connection.protocol.

Fixes bug 1243821

Change-Id: Ice3e7ad917c158a5953475809f3f46f48fd6054d
(cherry picked from commit c04ebd1a77d5dcf226812fadab08257207641220)
Merge "Fixes wrong Qpid protocol configuration" into stable/havana