DRY Dockerfiles via publishing the generated version

[balopat]

As @aslo pointed out, with the approach on docker-library, we could avoid duplications like this between our dockerfiles.

We could go as easy as providing a separate folder where the generated Dockerfile is visible for understandability, or as far as (I assume that's the goal in docker-library) the generated Dockerfile sits in the full folder structure, thus you can build the image using only docker.

I'd argue, this is a worthwile exercise to do, so that you don't need maven to build the image. You'd need maven only to generate the "image source", what is published to github as an artifact itself.