When using `docker compose run --entrypoint ''`, docker sends
`"Entrypoint": []` in the JSON. Podman currently treats that
as `nil` and fallback to default image entrypoint.
This is not what is expected by the user. Instead, it should
not use any entrypoint.
This commit fixes it by properly propagating the `[]` downstream
to libpod.
Fixes: #26078
Signed-off-by: Jan Kaluza <jkaluza@redhat.com>
3a981915f0