checkout seems to ignore my PATH

[marty-igolgi]

I am using a self-hosted runner with a private repo, which has submodules. My Git version is 2.7.4, which is reflected in my build logs. Git is in the path on my server, as it resides in /usr/bin and couldn't possibly not be in my path. In the event that the runner had it's own path, I set it explicitly with

    - uses: actions/checkout@v2
      with:
        submodules: 'recursive'
      env:
          PATH: /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin

Before that, I tried setting it with set-env. I can't find any explanation of where it's looking for PATH to not find it.