build(deps): bump pypa/gh-action-pypi-publish from 1.6.1 to 1.6.4

Bumps [pypa/gh-action-pypi-publish](https://github.com/pypa/gh-action-pypi-publish) from 1.6.1 to 1.6.4.
- [Release notes](https://github.com/pypa/gh-action-pypi-publish/releases)
- [Commits](pypa/gh-action-pypi-publish@5d1679f...c7f29f7)

---
updated-dependencies:
- dependency-name: pypa/gh-action-pypi-publish
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/cd.yml

@@ -84,7 +84,7 @@ jobs:
       - name: Publish binary wheel and source tarball on PyPI
         # Only attempt pypi upload in upstream repository
         if: github.repository == 'theupdateframework/python-tuf'
-        uses: pypa/gh-action-pypi-publish@5d1679fa6b895587c6eb10c3fe82205b440a580e
+        uses: pypa/gh-action-pypi-publish@c7f29f7adef1a245bd91520e94867e5c6eedddcc
         with:
           user: __token__
           password: ${{ secrets.PYPI_API_TOKEN }}