Checked out directory is always deleted when `path:` is used

[JLHasson]

I am checking out my repo using

    - name: Check out source repository
      uses: actions/checkout@v2
      with:
        path: some-relative-path

During a workflow run ${GITHUB_WORKSPACE}/some-relative-path exists & is checked out successfully. However, upon completion of the run this path is deleted & no longer exists. I followed the suggestion in #430 but I believe this is in reference to the cleanup before running the workflow. I am mostly interested in keeping the working directory around after the workflow has completed.

As far as I can tell without the path: command the working dir is kept around, it's unclear to my why it would be removed when path: is used, or how to disable this behavior.