changelog: add changelog entry for 8.16.1

[1pkg]

Motivation/summary

Add changelog entry for 8.16.1 release.

Checklist

• [x] Update CHANGELOG.asciidoc
• [x] Documentation has been updated

For functional changes, consider:

• Is it observable through the addition of either logging or metrics?
• Is its use being published in telemetry to enable product improvement?
• Have system tests been added to avoid regression?

How to test these changes

Related issues

[mergify[bot]]

backport-8.x has been added to help with the transition to the new branch 8.x. If you don't need it please use backport-skip label.