Add release notes for 1.3.16

[zelinh]

Is your feature request related to a problem? Please provide an existing Issue # , or describe. Add release notes for 1.3.16

Part of https://github.com/opensearch-project/opensearch-build/issues/4531

Check List

• [x] Backport Labels added.
• [ ] New functionality includes testing.
  • [ ] All tests pass
• [ ] New functionality has been documented.
  • [ ] New functionality has javadoc added
• [ ] Commits are signed per the DCO using --signoff

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