simplify gh workflow - do not run in container

Signed-off-by: Jack Luar <[email protected]>

Author: luarss

.github/workflows/github-actions-yaml-test.yml

@@ -9,13 +9,9 @@ jobs:
     name: 'Tests for variables.yaml'
     if: github.event_name == 'pull_request' || github.event_name == 'push'
     runs-on: ubuntu-latest
-    container:
-      image: openroad/ubuntu-cpp20
     steps:
     - name: Checkout repository
       uses: actions/checkout@v4
-      with:
-        submodules: 'recursive'
     - name: Run generate-variables-docs.py
       run: |
         python3 flow/scripts/generate-variables-docs.py