Remove DeterminateSystems/magic-nix-cache-action from GH actions

https://dtr.mn/magic-nix-cache-eol

Author: SFrijters

.github/workflows/compile-check-blink.yml

@@ -14,7 +14,6 @@ jobs:
     - uses: cachix/install-nix-action@v30
       with:
         github_access_token: ${{ secrets.GITHUB_TOKEN }}
-    - uses: DeterminateSystems/magic-nix-cache-action@v9
 
     - name: AppArmor fixes
       # Work around https://github.com/containers/bubblewrap/issues/632