remove github ci

Signed-off-by: gwg313 <gwg313@pm.me>

.github/workflows/nix.yml

@@ -1,11 +0,0 @@
-on: [push, pull_request]
-name: Basic Code Checks
-jobs:
-  formatting-check:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4.1.1
-      - uses: cachix/install-nix-action@v23
-        with:
-          nix_path: nixpkgs=channel:nixos-unstable
-      - run: nix develop --command alejandra --check .