Add missing test case for os-volume-attachment-update api

[Pranali Deore]

Recently due to commit ID - I3f2d98e9e473905a3de2f02e00c92ae3065e6ae7, nova os-volume-attachment-update api is broken.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/156515

[OpenStack Infra (hudson-openstack)]

Change abandoned by Ken'ichi Ohmichi (<email address hidden>) on branch: master
Review: https://review.openstack.org/156515
Reason: As http://lists.openstack.org/pipermail/openstack-dev/2016-May/096204.html , we start abandoning patches have gotten old without any updating after negative feedback. Please restore if necessary to restart this again.

[Ghanshyam Mann (ghanshyammann)]

Nice to have update attachment tests.

[Vishakha Agarwal (vishakha.agarwal)]

Hi,

I think the change has already been done for update_attached_volume testcase. We can close the bug.

https://github.com/openstack/tempest/blob/master/tempest/tests/lib/services/compute/test_servers_client.py#L567

Thanks.

[Martin Kopec (mkopec)]

Seems this got implemented by: https://review.opendev.org/#/c/283691/