Fix up to use proper name of the token

Author: gordonwatts

.github/workflows/pypi.yaml

@@ -25,5 +25,5 @@ jobs:
       - name: Publish servicex to PyPI
         uses: pypa/gh-action-pypi-publish@v1.6.4
         with:
-          password: ${{ secrets.pypi_password }}
+          password: ${{ secrets.PYPI_PASSWORD_SERVICEX }}
           print_hash: true