cachix action failing for unknown reasons, patch to use local runner

.github/workflows/nix.yml

@@ -24,6 +24,5 @@ jobs:
       - uses: actions/checkout@v3
       - run: nix-shell --run ./ci.sh
         env:
-          CI_PROJECT_PATH: pjjw
           CI_REGISTRY_AUTH: '${{ secrets.REGISTRY_AUTH }}'
           NIXPKGS_CHANNEL: '${{ matrix.channel }}'