Correct concurrency of gabbi tests for gabbi 1.22.0
Correct concurrency of gabbi tests for gabbi 1.22.0

When running gabbi under testr, concurrency grouping is controlled
by a regex in .testr.conf. A module name change in gabbi 1.22.0
inadvertently broke the grouping. This change should work for
old and new versions.

Change-Id: I9c875d8c73ccdfe633279914259061a8c3a7bf3d

openstack/aodh,openstack/aodh