docs: update changelog for 2.0.3 release

[udaya2899]

This PR updates the changelog on main to document the
2.0.3 release and moves the cherry-picked fix out of the
Unreleased section.

Companion to the release PR #3819 on the release/2.0 branch.

[gemini-code-assist]

Code Review

This pull request updates the CHANGELOG.md by moving a PyPI-related bug fix entry from the unreleased section into a new release section for version 2.0.3. The feedback suggests formatting the 'Fixes' keyword and its associated link on the same line to maintain consistency with other entries in the changelog.

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