Add Github action for release

.github/workflows/on-release.yml

@@ -0,0 +1,15 @@
+name: New release created
+on:
+  release:
+    types:
+      - created
+
+jobs:
+  update-homebrew:
+    name: Update homebrew formula
+    runs-on: ubuntu-latest
+    steps:
+    - uses: mislav/bump-homebrew-formula-action@v1
+      with: { formula-name: jenv }
+      env:
+        COMMITTER_TOKEN: ${{ secrets.BREW_TOKEN }}