[meta] Changelog Automation

[ArthurSens]

Thanks to @SachinSahu431, we advanced a lot in our project of changelog automation :)

We can't say it's complete though, since we haven't battle-tested the automation with a real release, and we also found a few things we'd like to clean up.

This issue is a meta issue, collecting all things we still want to do before declaring that "Changelog automation is completed".

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• [ ] #1547
• [ ] Do not comment on PR if the description is ok.
• [ ] #1548
• [ ] Go through all PR's merged since last release and add appropriate label
• [ ] Review and merge https://github.com/prometheus/client_golang/pull/1519
• [ ] Test automation in test branch

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In a very far future, we'd like to move this work to promu. Ideally continuing the work done in https://github.com/prometheus/promu/pull/170

[bwplotka]

Don't think it's completed

Did you mean to close as not planned @ArthurSens ?