Draft: Load a docker image as worker version

Works in a dedicated docker container which has access to docker socket:

docker run -it \
    -e CONFIG_PATH=/etc/arkindex.yml \
    -v /opt/arkindex/configuration.yml:/etc/arkindex.yml:ro \
    -v $(pwd)/import_docker_image.py:/tmp/import_docker_image.py \
    -v /var/run/docker.sock:/var/run/docker.sock \
    --network=services \
    --name=import-docker-image \
    registry.gitlab.com/teklia/arkindex/backend:1.4.2-binary \
    bash # to run in dev mode with <

The main issues are the requirements for tools:

• had to install docker in container (along with curl + gpg)
• and zstd

A better approach for that import would be to use internal python modules (docker & zstd), but that would probably require a custom docker image.