chore(deps): bump cachix/install-nix-action from 29 to 30 (#1388)

Bumps [cachix/install-nix-action](https://github.com/cachix/install-nix-action) from 29 to 30.
- [Release notes](https://github.com/cachix/install-nix-action/releases)
- [Commits](cachix/install-nix-action@v29...v30)

---
updated-dependencies:
- dependency-name: cachix/install-nix-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/nix.yml

@@ -13,7 +13,7 @@ jobs:
         with:
           submodules: true
       - name: nix
-        uses: cachix/install-nix-action@v29
+        uses: cachix/install-nix-action@v30
         with:
           nix_path: nixpkgs=channel:nixos-unstable
       - run: nix develop .#check -c make nix-tests
@@ -25,7 +25,7 @@ jobs:
         with:
           submodules: true
       - name: nix
-        uses: cachix/install-nix-action@v29
+        uses: cachix/install-nix-action@v30
         with:
           nix_path: nixpkgs=channel:nixos-unstable
       - run: nix develop .#fmt -c make nix-fmt