[8.16] 8.16.4 release notes (backport #6504)

[mergify]

Partially addresses #6503.

Preview: 8.16.4 release notes

---

This is an automatic backport of pull request #6504 done by Mergify.

[mergify]

Cherry-pick of b4aee1d has failed:

On branch mergify/bp/8.16/pr-6504
Your branch is up to date with 'origin/8.16'.

You are currently cherry-picking commit b4aee1d4.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   docs/release-notes/8.16.asciidoc

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   docs/release-notes.asciidoc

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

[github-actions]

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