chore(deps): bump cachix/install-nix-action from 24 to 25

Bumps [cachix/install-nix-action](https://github.com/cachix/install-nix-action) from 24 to 25.
- [Release notes](https://github.com/cachix/install-nix-action/releases)
- [Commits](cachix/install-nix-action@v24...v25)

---
updated-dependencies:
- dependency-name: cachix/install-nix-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/test.yml

@@ -35,7 +35,7 @@ jobs:
           - 29.1
           - snapshot
     steps:
-    - uses: cachix/install-nix-action@v24
+    - uses: cachix/install-nix-action@v25
       with:
         nix_path: nixpkgs=channel:nixos-unstable
     - uses: purcell/setup-emacs@master