Include a zip archive in releases

The Godot Asset Library can only accept zip files, so this creates a zip file and includes it in releases.

.github/workflows/build.yml

@@ -64,6 +64,7 @@ jobs:
         run: |
           mkdir dist
           tar -czvf dist/godot-pure-data-universal.tar.gz -C package-contents .
+          zip -r dist/godot-pure-data-universal.zip package-contents
       - name: create release
         uses: softprops/action-gh-release@v2.0.8
         with: