The tripleo-docker-rm role has been replaced by tripleo-container-rm [0].
This role will identify the docker engine via the container_cli variable
and perform a deletion of that container. However, these tasks inside the
post_upgrade_tasks section were thought to remove the old docker containers
after upgrading from rocky to stein, in which podman starts to be the
container engine by default.
For that reason, we need to ensure that the container engine in which the
containers are removed is docker, as otherwise we will be removing the
podman container and the deployment steps will fail.
Closes-Bug: #1836531
[0] - 2135446a35
Depends-On: https://review.opendev.org/#/c/671698/
Change-Id: Ib139a1d77f71fc32a49c9878d1b4a6d07564e9dc
d1035703b7