All artifacts in release download folder should come from the release pipeline

We have made great improvements to the release process over the last few years but there are still a few rough corners which make debugging issues with releases a bit tricky.

For the record, the scripts for downloading release artifacts and uploading them are here - https://gitlab.haskell.org/bgamari/ghc-utils/-/tree/master/rel-eng

• fetch-gitlab-arifacts/ - contains the scripts for getting the artifacts from gitlab
• upload.sh - contains the scripts for uploading the artifacts to the right place

Three issues I know about

• docs/ folder is not generated from doc-tarball job (#21510 (closed))

• src and testsuite not generated from the source-dist job (#21511 (closed))

• hackage docs are not created by a CI pipeline (#21493 (closed))

This is a meta ticket to track these kinds of issues