roles: introduce `ceph-container-engine` role

roles: introduce `ceph-container-engine` role

This commit splits the current `ceph-container-common` role.

This introduces a new role `ceph-container-engine` which handles the
tasks specific to the installation of containers tools (docker/podman).

This is needed for the ceph-dashboard implementation for 2 main reasons:

1/ Since the ceph-dashboard stack is only containerized, we must install
everything needed to run containers even in non containerized
deployments. Splitting this role allows us to not have to call the full
`ceph-container-common` role which would run a bunch of unneeded tasks
that would have been skipped anyway.

2/ The current implementation would have required to run
`ceph-container-common` on all ceph-clients nodes which would have been
conflicting with 9d3517c670ea2e944565e1a3e150a966b2d399de (we don't want
to run ceph-container-common on all client nodes, see mentioned commit
for more details)

Signed-off-by: Guillaume Abrioux <gabrioux@redhat.com>
(cherry picked from commit 55420d6253bc6605738fe3f4745e2ba08a6ea5b8)