ci: added stable tag that gets moved with every release

Author: folke

Diff for: .github/workflows/ci.yml

@@ -59,3 +59,13 @@ jobs:
         with:
           release-type: simple
           package-name: lazy.nvim
+      - name: tag stable versions
+        if: ${{ steps.release.outputs.release_created }}
+        run: |
+          git config user.name github-actions[bot]
+          git config user.email github-actions[bot]@users.noreply.github.com
+          git remote add gh-token "https://${{ secrets.GITHUB_TOKEN }}@github.com/google-github-actions/release-please-action.git"
+          git tag -d stable || true
+          git push origin :stable || true
+          git tag -a stable -m "Last Stable Release"
+          git push origin stable