Bump cachix/install-nix-action from V27 to 29

Bumps [cachix/install-nix-action](https://github.com/cachix/install-nix-action) from V27 to 29. This release includes the previously tagged commit.
- [Release notes](https://github.com/cachix/install-nix-action/releases)
- [Commits](cachix/install-nix-action@V27...v29)

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

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/release.yml

@@ -12,7 +12,7 @@ jobs:
       - uses: actions/checkout@master
         with:
           fetch-depth: 0
-      - uses: cachix/install-nix-action@V27
+      - uses: cachix/install-nix-action@v29
       - name: Get release notes
         id: release-notes
         run: ./scripts/print-release-notes.sh ${{ github.ref }}

.github/workflows/test.yml

@@ -13,7 +13,7 @@ jobs:
     steps:
     - uses: actions/checkout@v4
     - name: Install nix
-      uses: cachix/install-nix-action@V27
+      uses: cachix/install-nix-action@v29
     - run:
         nix-build -I nixpkgs=https://github.com/NixOS/nixpkgs/archive/nixpkgs-unstable.tar.gz
     - run: