add settings for rockylinux, rename var names to el8 prefix

1 job for 5-prepare-role-for-rocky-linux in 2 minutes and 21 seconds (queued for 2 seconds)
Name Stage Failure
molecule Test
TASK [Delete docker network(s)] ************************************************

PLAY RECAP *********************************************************************
localhost : ok=2 changed=2 unreachable=0 failed=0 skipped=1 rescued=0 ignored=0

INFO Pruning extra files from scenario ephemeral directory
Cleaning up project directory and file based variables
ERROR: Job failed: exit code 1