Add GitHub release step to workflow

Clarify the existing step name to 'Build and publish to PyPI' and add a new CI step that tags the repo and creates a GitHub Release using the built dist/* artifacts. The new step uses GH_TOKEN and the version from steps.version_check.outputs.version to push a v<version> tag and run `gh release create`, automating GitHub releases whenever the package version changes.

Author: kozo2

.github/workflows/release.yml

@@ -34,11 +34,22 @@ jobs:
       run: |
         python -m pip install --upgrade pip
         pip install setuptools wheel twine
-    - name: Build and publish
+    - name: Build and publish to PyPI
       if: steps.version_check.outputs.changed == 'true'
       env:
         TWINE_USERNAME: ${{ secrets.PYPI_USERNAME }}
         TWINE_PASSWORD: ${{ secrets.PYPI_PASSWORD }}
       run: |
         python setup.py sdist bdist_wheel
         twine upload dist/*
+    - name: Create GitHub Release
+      if: steps.version_check.outputs.changed == 'true'
+      env:
+        GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      run: |
+        VERSION=${{ steps.version_check.outputs.version }}
+        git tag "v${VERSION}"
+        git push origin "v${VERSION}"
+        gh release create "v${VERSION}" dist/* \
+          --title "v${VERSION}" \
+          --generate-notes