Fetch origin/main for Spotless ratchet in publish workflow (#119)

Author: jingtang10

.github/workflows/publish.yml

@@ -9,6 +9,8 @@ jobs:
     steps:
       - name: Check out code
         uses: actions/checkout@v4
+      - name: Fetch origin/main for Spotless ratchet
+        run: git fetch origin main
       - name: Set up JDK 21
         uses: actions/setup-java@v4
         with: