Cinder is failing after upgrade to Juno. This is because of the
following race conditions:
- Cinder takes time to update the current status of the services.
- Cinder sometimes gets stuck at creating block device.
- While creating block device, deleting that device is not allowed.
This creates error and stops the script from running.
Fixes include some helper functions which adds to the robustness of
cinder test cases.
Co-Authored-By: Roger Luethi <rl@patchworkscience.org>
Change-Id: I3254438fdac0bd4a7f927f0f203c51ab6e45b9c0
5b9891d5d5