keep latest branch up to date

.github/workflows/release.yml

@@ -37,8 +37,16 @@ jobs:
 
       - name: Send a Discord notification if a publish happens
         if: steps.changesets.outputs.published == 'true'
+        id: discord-notification
         env:
           DISCORD_WEBHOOK: ${{ secrets.DISCORD_WEBHOOK }}
         uses: Ilshidur/action-discord@0.3.2
         with:
-          args: 'A new release just went out! [Release notes →](<https://github.com/snowpackjs/astro/releases/>)'
+          args: 'A new release just went out! [Release notes →](<https://github.com/snowpackjs/astro/releases/>)'
+
+      - name: push main branch to latest branch
+        if: steps.changesets.outputs.published == 'true'
+        id: git-push-latest
+        # Note: this will fail if "latest" and "main" have different commit history,
+        # which is a good thing! Also, don't push if in pre-release mode.
+        run: '(test -f .changeset/pre.json && echo "prerelease: skip pushing to latest branch.") || git push origin main:latest'