chore(deps): bump cachix/install-nix-action from V27 to 28

Bumps [cachix/install-nix-action](https://github.com/cachix/install-nix-action) from V27 to 28. This release includes the previously tagged commit.
- [Release notes](https://github.com/cachix/install-nix-action/releases)
- [Commits](cachix/install-nix-action@V27...V28)

---
updated-dependencies:
- dependency-name: cachix/install-nix-action
  dependency-type: direct:production
...

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

.github/workflows/build.yml

@@ -35,7 +35,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Insall nix
-        uses: cachix/install-nix-action@V27
+        uses: cachix/install-nix-action@V28
         with:
           install_url: https://releases.nixos.org/nix/nix-2.18.2/install
           extra_nix_config: |

.github/workflows/pr.yml

@@ -33,7 +33,7 @@ jobs:
           fetch-depth: 0
 
       - name: Install nix
-        uses: cachix/install-nix-action@V27
+        uses: cachix/install-nix-action@V28
         with:
           install_url: https://releases.nixos.org/nix/nix-2.18.2/install
           extra_nix_config: |