scenario002: updating volume encryption provider
scenario002: updating volume encryption provider

https://review.openstack.org/#/c/416672 made the new luks provider required.
Let's use it.

Closes-Bug: #1658755
Change-Id: Icc7c3c933af6621959ce3e6af99c73b4afd87509

dprince/tripleo-heat-templates,dprince/tripleo-heat-templates,openstack/tripleo-heat-templates,openstack/tripleo-heat-templates