enable Longhorn in emulated baremetal CI
Related to #335 (closed)
This is a first step only, it enables longhorn, but does not yet make any component use longhorn PVs.
Further steps will be done with !999 (closed) .
(This depends on sylva-projects/sylva-elements/container-images/libvirt-metal!6 (merged))
Edited by Thomas Morin