Removes git-submodules artifacts (#10321)

Author: sobolevn

.github/workflows/test.yml

@@ -35,8 +35,6 @@ jobs:
 
     steps:
     - uses: actions/checkout@v2
-      with:
-        submodules: true
     - uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python }}

.github/workflows/test_stubgenc.yml

@@ -20,13 +20,10 @@ jobs:
 
     - uses: actions/checkout@v2
 
-    - name: initialize submodules
-      run: git submodule update --init
-
     - name: Setup 🐍 3.8
       uses: actions/setup-python@v2
       with:
         python-version: 3.8
 
     - name: Test stubgenc
-      run: misc/test-stubgenc.sh
+      run: misc/test-stubgenc.sh