build: action 中增加 submodule 更新步骤

.github/workflows/build-push.yml

@@ -18,6 +18,8 @@ jobs:
     name: Build Docker Image and Push
     steps:
     - uses: actions/checkout@v2
+    - name: Checkout submodules
+      run: git submodule update --init --recursive
     - name: Inject slug/short variables
       uses: rlespinasse/github-slug-action@v3.x
     - name: Cache node modules