Previously, Podman could be selected through automatic driver detection or with
`mise run gateway -- --driver podman`, but it did not have a dedicated task
like the Docker and VM drivers.
This adds a gateway:podman task and moves the Podman-specific setup into its
own script. The generic gateway task now delegates Podman launches to that
script.
Additionally:
Unlike Docker, which rebuilds and bind-mounts the supervisor binary, Podman
uses a dev-tagged supervisor image that can become stale. The default Podman
supervisor image is therefore rebuilt on each launch.
Signed-off-by: Kris Hicks <khicks@nvidia.com>
Drew Newberry