Add support for buildkit + kubernetes

[davidferlay]

Observed

• Building the image of an action using a local Dockerfile uses docker build
• Running the image as a container uses docker run

Expected

It would be great to support

• buildkit > to remplace docker build
• kubernetes (CRI?) > to remplace container run

Later on, we could also add additional support for containerd

[andypost]

FYI Drupal selected to use buildah in kubernertes runner as this is only (ATM) runtime that can build without special privileges, ref https://docs.gitlab.com/ee/ci/docker/using_docker_build.html#docker-alternatives