actions update

.forgejo/workflows/demo.yaml

@@ -6,14 +6,7 @@ jobs:
       - name: checkout
         uses: actions/checkout@v3
 
-      - uses: https://git.madhouse-project.org/actions/nix/install@main
+      - uses: cachix/install-nix-action@v27
         with:
-          install-url: "https://nixos.org/nix/install"
+          nix_path: nixpkgs=channel:nixos-unstable
-
+        - run: nix develop
-      - name: Run something in a development environment
-        uses: https://git.madhouse-project.org/actions/nix/develop@main
-        with:
-          flake: .
-          package: # no default, see above
-          run: |
-            # No default here, either!