Propose an alternative Dockerfile where the only user is root

[dlonguet]

In order to have a docker image which runs correctly in any environment and for any docker daemon even rootless, the easiest solution, even if not ideal, would be to build a docker where the only user is root and everything is installed for root.

When I naively try to remove any mention to user diver in the current Dockerfile, the image does not build. The build fails at the end when trying to pin every seacoral package:

[ERROR] Package conflict:
missing dependency:
- (request) -> seacoral
unknown package
...
make: error 20
The command '/bin/bash -l -c make -C seacoral reset-version
...
returned a non-zero code : 2

Could you please provide such a Dockerfile, as an alternative to the current one?