site-container: update container-engine role

site-container: update container-engine role

Since the split between container-engine and container-common roles,
the tags and condition were not updated to reflect the change.

- ceph-container-engine needs with_pkg tag
- ceph-container-common needs fetch_container_images
- we don't need to pull the container image in a dedicated task for
atomic host. We can now use the ceph-container-common role.

Signed-off-by: Dimitri Savineau <dsavinea@redhat.com>
(cherry picked from commit 2d375e1aa779e19a39ac435d7064133add07c3ce)