* Empty commit for release pull request
* Update compatibility sections and add release 9.0.0 changelog
* Add testing instructions for the 9.0.0 release
* Update testing instructions for the 9.0.0 release
* Remove testing instructions for an unmerged PR
* Bumping version strings to new version.
Co-authored-by: github-actions <github-actions@github.com>
Co-authored-by: Daniel Dudzic <daniel.dudzic@automattic.com>