Podman support for Runner

RHEL8 does not support and include the docker package. This causes issues for customers who want to set up runners on RHEL8 and potential future situations from Oracle linux where docker is no longer supported.

As of now, there is a workaround to setup docker but this is just a workaround at this point:

• https://access.redhat.com/solutions/3696691
• https://docs.docker.com/engine/install/rhel/z

Potentially, these workarounds may not be available in the future. As such, podman support for runner would be appreciated.