When we want to create a large set of containers at the same time, an
action plugin can now be used which will call the podman_container
module.
The podman_containers action plugin takes a list of containers with
pre-defined parameters ready to be consumed by the podman_container
module.
The podman_containers module is just useful for Ansible documentation.
The molecule tests will ensure that the action plugin actually works and
creates the 3 containers.
Change-Id: I1e6881f3871a7a125db9374c608ecad0bafcb882