Update DeterminateSystems/magic-nix-cache-action action to v9 (#49)

Author: SuperSandroBot

.github/workflows/ci.yaml

@@ -39,7 +39,7 @@ jobs:
           sed -i'' "s/0\\.0\\.0-git/${{ steps.meta.outputs.version }}/" Cargo.lock
 
       - uses: cachix/install-nix-action@v30
-      - uses: DeterminateSystems/magic-nix-cache-action@v8
+      - uses: DeterminateSystems/magic-nix-cache-action@v9
         with:
           diagnostic-endpoint: false
           use-flakehub: false