3.5.2 is not available any more on dlcdn.apache.org, plus we run 3.6
in production.

Kafka 3.5.0 has been removed from the Apache CDN.

It is required to run the full swh-environment tests suites.

We no longer build debian packages for swh components so we can
safely remove the build of these docker images.

Debian official package for nodejs 18.x superseeded the one
from nodesource so npm must now be explicitly installed.

Nevertheless, update nodesource package setup but comment it
until we have to bump nodejs version.

See https://github.com/nodesource/distributions#new-update-%EF%B8%8F.

A stage can only appear once per Dockerfile, so `FROM identifier` must
be unique. Move building rage upward for convenience.

Also document why we don’t pin rage to a specific version number.

Testing recovery bundles in swh-alter requires `rage` and `rage-keygen`.
See: https://github.com/str4d/rage/blob/main/rage/Cargo.toml

We use rust official Docker image to build the software via `cargo
install` in a dedicated stage. We then copy the (statically linked)
binaries to our image.

It is required by swh-lister to list CRAN packages.

This avoids having to hardcode it in the swh-jenkins-jobs repo.

This is needed by opam init.

pyenv doesn't keep the old betas around, using the -dev version should
be more stable until there's a 3.12 release

This allows testing for updates of dependent images

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1030129 now reliably
triggers, with the openjdk update in security.debian.org. Work around it
by installing the headless jre in the first stage.

This reverts commit 7b3dea4a.

Finally, using sphinx-carousel turned out better suited for the needs
of swh-alter documentation.

The swh-alter documentation wants to use `convert`.