Copy release notes for v16.0.1, v15.0.3, and v14.0.5

[GuptaManan100]

Description

This PR copies the release notes for v16.0.1, v15.0.3 and v14.0.5.

[vitess-bot]

Review Checklist

Hello reviewers! 👋 Please follow this checklist when reviewing this Pull Request.

General

• Ensure that the Pull Request has a descriptive title.
• If this is a change that users need to know about, please apply the release notes (needs details) label so that merging is blocked unless the summary release notes document is included.
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Bug fixes

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Non-trivial changes

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Backward compatibility

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