Merge pull request #439 from xmonad/dependabot/github_actions/cachix/install-nix-action-19

build(deps): bump cachix/install-nix-action from 18 to 19

.github/workflows/nix.yml

@@ -12,7 +12,7 @@ jobs:
       contents: read
     steps:
       - name: Install Nix
-        uses: cachix/install-nix-action@v18
+        uses: cachix/install-nix-action@v19
         with:
           install_url: https://nixos-nix-install-tests.cachix.org/serve/i6laym9jw3wg9mw6ncyrk6gjx4l34vvx/install
           install_options: '--tarball-url-prefix https://nixos-nix-install-tests.cachix.org/serve'