Update .github/workflows/update.yml

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: wu21-web

.github/workflows/update.yml

@@ -30,5 +30,5 @@ jobs:
           git config --global user.email "github-actions[bot]@users.noreply.github.com"
           git add project-structure.txt
           git commit -m "Update project structure" || echo "No changes to commit"
-          git push origin HEAD:main
+          git push origin HEAD