update ci to latest cachix-action, remove macos

* macos was failing for some reason and breaking the whole CI
* don't need to ignore the cachix-action file anymore

.github/workflows/ci.yaml

@@ -4,15 +4,13 @@ on:
   push:
 jobs:
   tests:
-    strategy:
-      matrix:
-        os: [ubuntu-latest, macos]
-    runs-on: ${{ matrix.os }}
+    runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
     - uses: cachix/install-nix-action@v8
-    - uses: cachix/cachix-action@v5
+    - uses: cachix/cachix-action@v6
       with:
         name: nixpkgs-update
         signingKey: '${{ secrets.CACHIX_SIGNING_KEY }}'
         authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
+    - run: nix-build

.gitignore

@@ -5,5 +5,4 @@
 /result
 dist-newstyle/
 dist/
-store-path-pre-build
 test_data/actual*