Add PRs with release-notes labels to the CHANGELOG

[lucacome]

Proposed changes

Problem: Looking for all the PRs that have the release-notes label is a manual process

Solution: As a first step in automating this process, we add the list of PRs to the top of the CHANGELOG so they can be manually moved to the appropriate sections

Checklist

Before creating a PR, run through this checklist and mark each as complete.

• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works
• I have checked that all unit tests pass after adding my changes
• I have updated necessary documentation
• I have rebased my branch onto main
• I will ensure my PR is targeting the main branch and pulling from my branch from my own fork

Release notes

If this PR introduces a change that affects users and needs to be mentioned in the release notes,
please add a brief note that summarizes the change.

NONE