Fixes missing long description in package metadata and PyPI page

Checklist

• The commits follow the conventional commits specification.
• You ran the linters with prek.
• You wrote unit test to demonstrate the bug you are fixing, or to stress the feature you are bringing. N/A
• You reached 100% of code coverage on the code you edited, without abusive use of pragma: no cover N/A
• If this PR is about a new feature, or a behavior change, you have updated the documentation accordingly. N/A

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