Test that the image volume cache for cinder in RHOSO can be configured by adding the necessary parameters to both the DEFAULT and relevant back end sections of the cinder volume service in the OpenStackControlPlane CR file. 
See the associated Epic for these settings.

Then test that this image volume cache works as expected: 

When enabled, the Image-Volume cache stores a copy of an image the first time a volume is created from it. This stored image is cached locally to the Block Storage back end to help improve performance the next time this image is used to create a volume. You can set the limits of the Image-Volume cache to a size in GB, or number of images, or both.

The Image-Volume cache is supported by several back ends. 

When the image volume cache has been configured and is working as expected, send the cinder technical writer the configured DEFAULT and relevant back end sections of the cinder volume service in the OpenStackControlPlane CR file so that this can be added as an example to the documentation of this feature.

Acceptance Criteria: 

• Enable the image-volume cache in downstream CI
• Running tempest tests that uses images multiple times in that job
• RHOSO 18 documentation how to use image-volume cache