Switch volume delete to use the ID

Switch volume delete to use the ID

At the moment, the current code that's used when deleting volumes
uses a function that attempts to pull by ID, and then falls back
to name.

This is potentially dangerous because it might match more than one
volume and therefore potentially delete the wrong volume.  This
patch revises the code to enforce retrieving the volume based on
the ID instead which is globally unique.

The tools that leverage this inside releng-global-jjb already
provide an ID at the moment[1].

[1]: https://github.com/lfit/releng-global-jjb/blob/d22d069117b64cee73be1165861013de9e79ab19/shell/openstack-cleanup-orphaned-volumes.sh#L18

Change-Id: I078c8c4447ac308c66678e86ae31e8947f40340e
Signed-off-by: Mohammed Naser <mnaser@vexxhost.com>