ci: bump cachix/install-nix-action from 26 to 27 (#197)

Bumps [cachix/install-nix-action](https://github.com/cachix/install-nix-action) from 26 to 27.
- [Release notes](https://github.com/cachix/install-nix-action/releases)
- [Commits](https://github.com/cachix/install-nix-action/compare/v26...V27)

---
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>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/ci.yml

@@ -39,7 +39,7 @@ jobs:
           echo "rev=$(git rev-parse --short HEAD)" >> "$GITHUB_OUTPUT"
 
       - name: Install Nix
-        uses: cachix/install-nix-action@v27
+        uses: cachix/install-nix-action@V27
 
       - name: Format changes
         run: |

.github/workflows/website.yml

@@ -17,7 +17,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Install Nix
-        uses: cachix/install-nix-action@v26
+        uses: cachix/install-nix-action@V27
 
       - name: Setup cache
         uses: DeterminateSystems/magic-nix-cache-action@v6