Bump cachix/install-nix-action from 23 to 25

Bumps [cachix/install-nix-action](https://github.com/cachix/install-nix-action) from 23 to 25.
- [Release notes](https://github.com/cachix/install-nix-action/releases)
- [Commits](https://github.com/cachix/install-nix-action/compare/v23...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/deploy.yml

@@ -16,7 +16,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v4
-    - uses: cachix/install-nix-action@v23
+    - uses: cachix/install-nix-action@v25
       with:
         nix_path: nixpkgs=channel:nixos-stable
         extra_nix_config: |

.github/workflows/test.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v4
-    - uses: cachix/install-nix-action@v23
+    - uses: cachix/install-nix-action@v25
       with:
         nix_path: nixpkgs=channel:nixos-stable
         extra_nix_config: |