Check the debug logs for some methods in the cinder and nova helpers to
reproduce the erros described in bug [1]. The logger is disabled by default,
so the error was being ignored, in order to show the error, the logger
needs to be enabled for the tests in question. The logging was disabled
by allembic configuring logging in [2], so this patch also removes that
logging config to expose the errors.
[1] https://bugs.launchpad.net/watcher/+bug/2110149.
[2] https://github.com/openstack/watcher/blob/master/watcher/db/sqlalchemy/alembic/env.py#L26
Change-Id: I3598ca1d08d260602c392f8a8098821faa53f570