checkout submodules

.github/workflows/backend_build.yml

@@ -19,6 +19,8 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v2
+        with:
+          submodules: true
 
       - name: Set up JDK
         uses: actions/setup-java@v1

.github/workflows/deploy.yml

@@ -19,6 +19,8 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v2
+        with:
+          submodules: true
 
       - name: Set up JDK
         uses: actions/setup-java@v1

.github/workflows/frontend_build.yml

@@ -19,6 +19,8 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v2
+        with:
+          submodules: true
 
       - name: Set up Node
         uses: actions/setup-node@v2