Release 3.9.0

[benoit74]

• Secure the CI is green on git main
• Update version in pyproject.toml to x.x.x (remove -devx suffix)
• Update Github milestone to match the issues that will be released
• Close Github milestone
• Update the Changelog so that it is in line with the content of Github milestone and does not have [Unreleased] section anymore
• Push a tag on Github named vx.x.x
• Create a Github release, pointing to the tag, with the Changelog of this release
• Publish the Github release (this will trigger the CI, if the CI fails and you have to push a minor fix which does not justify to create a new version, you will have to delete the release and re-create it from scratch)
• Review and approve release workflow at https://github.com/openzim/python-libzim/actions
• Check that version is published as a Github release at https://github.com/openzim/python-libzim/releases
• Check that version is published on Pypi at https://pypi.org/project/libzim/
• Create a new Github milestone with the next minor version incrementaly
• Create a new Github issue attached to this milestone with this checklist inside
• Create new ## [Unreleased] section in Changelog (placeholder for future entries)
• Adjust version in pyproject.toml to x.y.z+1-dev0 (next patch)
• Push both changes to main branch
• Advertise this new version on Slack