fix(ci): add rebase before push in release workflow

The "Generate contributor notes" step pushes CONTRIBUTORS.md to main
without pulling first. When two releases run concurrently, the second
push fails with non-fast-forward. Add git pull --rebase before push
to handle the race.

Co-authored-by: Copilot <[email protected]>

Author: jongio

.github/workflows/release.yml

@@ -101,6 +101,7 @@ jobs:
           if ! git diff --quiet CONTRIBUTORS.md; then
             git add CONTRIBUTORS.md
             git commit -m "docs: update CONTRIBUTORS.md for $NEW_TAG"
+            git pull --rebase origin main
             git push origin HEAD:main
           fi