Releasing 9.0.0

[andresesfm]

@hyochan, @jeremybarbet. I want to get your thoughts on releasing 9.0.0 as the last RC (4) was well received by people who tested it.

I have prepared the following PR with all the changes needed for this: #1843. Note that it is not a direct merge from next for the following reason @jeremybarbet brought up: #1838 . I suggest the following:

1. Merge the new PR and release 9.0.0 to move forward
2. @hyochan to reset next to the new main branch
3. @jeremybarbet to rebase and create PRs against the new next branch with his breaking changes in preparation for the next major release.

Let me know what you think

[jeremybarbet]

That's sounds good to me. Well done for publishing v9!

It's also better to release, even major version, without thousands of changes. I will continue working on my 2 PRs I have open, and we can release them as v10 once completed.

2. I don't think that's necessary anymore, since v9 is now landed in main, we can just merge main into next, and use next for the next major release

[andresesfm]

@jeremybarbet 2 is still needed. There's no other way to reconcile main and next