Change the way version tagging works

[lmoureaux]

Is your feature request related to a problem? Please describe.

The current way of doing versions has several issues:

• The release notes are not transparent
• We have difficulties getting AutoRevision to work properly in all cases (see AutoRevision update #1820 for latest attempt)

I think this is due to a fundamental problem with the way we try to handle this.

Describe the solution you'd like

A new version would be made as follows:

• Create a new PR with a distinctive format such as a version tag
• In the PR, create and fill a file NEWS.md with the release notes
• In the PR, update AutoRevision.txt to the new version
• Upon merging, an automatic action starts a new release at the tip of the branch, adds the release notes from NEWS.md
• The release is made public automatically once all binary packages are available

This way, the release will always be made from a commit with the correct version.

Describe alternatives you've considered

Current one, but seems fundamentally broken.

Additional context
Add any other context or screenshots about the feature request here.

[jwrober]

The workflow I use for a release today makes doing all of this a bit difficult. Once we get a few PRs done I typically open a draft release and begin the process of capturing the closed PRs and organizing them into relevant sections. I keep a note at the top to help me remember what the last PR ID was that was added to the draft release. This helps with the counting effort as part of our documented release process. Doing it this way "feels" easier than holding a draft PR open or some such with commits to a NEWS.md file.

So what if we changed the order of operations a bit? Get rid of the action to auto-create the PR for the update to AutoRevision.txt at the release tag event, and instead add a manual update to AutoRevision.txt as a precursor step to tagging the release. With the file in the repo at HEAD, the existing code should find the appropriate tag to set the version correctly.