Using submodules in actions/checkout@v2 for private Repos

workflow.yml

- name: Checkout code
  uses: actions/checkout@v2
  with:
    submodules: <<true | recursive>>
    # Generate a personal access token from https://github.com/settings/tokens
    # Added that token as a secret in your repo at https://github.com/<<username>>/<<repo>>/settings/secrets/new
    # In the token key below, access the same token using secrets.<<YOUR_SECRET_NAME>>
    token: ${{ secrets.MY_ACCOUNT_PAT }}

    # For more reference see 
    # - https://github.com/actions/checkout/issues/116#issuecomment-644419389
    # - https://github.com/actions/checkout/issues/116