[bug] Option sparse-checkout-cone-mode is not honored correctly when using git < 2.37

[samkearney]

To reproduce:

On a runner/image with git < 2.37 (for example, Ubuntu 22.04):

on: push

jobs:
  test:
    runs-on: ubuntu-latest
    container:
      image: ubuntu:22.04
    steps:
      - run: |
          apt-get update
          apt-get install -y git tree
      - uses: actions/checkout@v4
        with:
          sparse-checkout: subdir/subdir
          sparse-checkout-cone-mode: true
      - run: |
          echo "Sparse checkout: $(git config --get core.sparseCheckout)"
          echo "Cone mode: $(git config --get core.sparseCheckoutConeMode)"
          tree

Expected Results: Checked-out tree contains top-level files in the repo, per the sparse-checkout documentation on cone mode
Results: Only subdirectory specified is present in the tree

Note: Cone mode became the default in Git 2.37. In earlier versions of Git, cone mode needs to be set explicitly to work (e.g. git sparse-checkout set --cone). But the Checkout action is not doing this.

[samkearney]

Reproducing repo: https://github.com/samkearney/actions-checkout-sparse-reproducer