Allow kwargs in create_volume_snapshot
Allow kwargs in create_volume_snapshot

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

Implements: blueprint tempest-scenario-manager-stable
Change-Id: Ib58a6125b34adb932e1f282ebab6a79a6906dd73

openstack/tempest,openstack/tempest