Allow kwargs in create_volume

As a part of the scenario/manager.py stabilization tracked by
the below BP the patch adds kwargs argument for create_volume
method so that the consumers are able to pass additional
parameters if needed.

Closes-Bug: #1899753
Implements: blueprint tempest-scenario-manager-stable
Change-Id: I36107992256bd6816b2ab2e40b783279952c6eeb
1 file changed