- adds submodules checkout to workflow

Author: baywet

.github/workflows/dotnetcore.yml

@@ -13,6 +13,8 @@ jobs:
 
     steps:
     - uses: actions/checkout@v2
+    - name: Checkout submodules
+      uses: textbook/git-checkout-submodule-action@master
     - name: Setup .NET Core
       uses: actions/setup-dotnet@v1
       with: