chore(deps): update cachix/install-nix-action action to v31 (#88)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/templates.yml

@@ -28,7 +28,7 @@ jobs:
         os: [ ubuntu-latest, macos-latest ]
         folder: ${{ fromJSON(needs.find-templates.outputs.folders) }}
     steps:
-      - uses: cachix/install-nix-action@v30
+      - uses: cachix/install-nix-action@v31
       - uses: actions/checkout@v4
       - run: nix flake check --override-input blueprint ../..
         working-directory: ${{ matrix.folder }}