made github cmake runner fetch submodules (#906)

.github/workflows/cmake.yml

@@ -31,6 +31,8 @@ jobs:
       - name: Fix Checkout
         run: |
           git fetch --force --tags
+          git submodule init
+          git submodule update
 
       - name: Create Build Environment
         # Some projects don't allow in-source building, so create a separate