Removes broken GitHub Actions workflow

.github/workflows/test.yml

@@ -1,19 +0,0 @@
-name: "Test"
-on:
-  pull_request:
-  push:
-jobs:
-  tests:
-    runs-on:
-    - ubuntu-latest
-    - macos-latest
-    steps:
-    - uses: actions/checkout@v3
-    - uses: cachix/install-nix-action@v20
-      with:
-        nix_path: nixpkgs=channel:nixos-unstable
-    - uses: cachix/cachix-action@v12
-      with:
-        name: willemml
-        authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
-    - run: nix run .#home-build