CI: Generate release

This isn't perfect since we need some way to generate the body of the
release, but it's much better than doing it manually.

Signed-off-by: Stephen Finucane <stephen@that.guru>

Author: stephenfin

.github/workflows/ci.yaml

@@ -83,3 +83,23 @@ jobs:
         uses: pypa/gh-action-pypi-publish@master
         with:
           password: ${{ secrets.PYPI_API_TOKEN }}
+      - name: Create release on GitHub
+        if: startsWith(github.ref, 'refs/tags')
+        uses: actions/create-release@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          tag_name: ${{ github.ref }}
+          release_name: ${{ github.ref }}
+          draft: false
+          prerelease: false
+      - name: Add sdist to release
+        if: startsWith(github.ref, 'refs/tags')
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.create_release.outputs.upload_url }}
+          asset_path: ./dist/git-pw-${{ github.ref }}.tar.gz
+          asset_name: git-pw-${{ github.ref }}.tar.gz
+          asset_content_type: application/gzip