fix: prevent crash if no update in submodule

.github/workflows/deploy.yml

@@ -30,6 +30,7 @@ jobs:
         with:
           node-version: 18.14
       - name: Fetch submodules
+        continue-on-error: true
         run: |
           git submodule update --init --recursive --checkout -f --remote -- "content"
           git config --global user.name "GitHub Action"