Update GitHub Actions workflow to use PyPI API token for publishing

Author: fcakyon

.github/workflows/publish_pypi.yml

@@ -20,8 +20,8 @@ jobs:
         pip install setuptools wheel twine
     - name: Build and publish
       env:
-        TWINE_USERNAME: ${{ secrets.PYPI_USERNAME }}
-        TWINE_PASSWORD: ${{ secrets.PYPI_PASSWORD }}
+        TWINE_USERNAME: __token__
+        TWINE_PASSWORD: ${{ secrets.PYPI_API_TOKEN }}
       run: |
         python setup.py sdist bdist_wheel
         twine upload --verbose --skip-existing dist/*