add release notes 4.16

[tungmhoang]

Summary

• Add release notes for 4.16. Preview link: http://10.2.7.208/release-notes/kobiton-four-latest

  Related PRs, issues, or features (optional)

• https://kobiton.atlassian.net/browse/KOB-47138

Metadata

• [x] Adds new file(s)
• [x] Edits existing file(s)
• [x] Removes file(s)

PR contributor checklist

• [x] My PR follows the Kobiton Docs contributor guidelines, meaning:

  • My content contains correct spelling and grammar.
  • My directories and files are named and structured correctly.
  • My style and voice follows the Microsoft Style Guide.
  • I added all new pages to their section's nav.adoc file.
  • I removed all localizations (like en-us) from my URLs.