Bump cachix/install-nix-action from 29 to 30

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] <support@github.com>

.github/workflows/python-app.yml

@@ -42,7 +42,7 @@ jobs:
  Add-Content $env:GITHUB_PATH "$env:LOCALAPPDATA\Microsoft\WinGet\Packages\NGSpice.NGSpice__DefaultSource\Spice64\bin"
  - name: Install Nix for Ubuntu
  if: ${{runner.os != 'Windows' }}
- uses: cachix/install-nix-action@v29
+ uses: cachix/install-nix-action@v30
  with:
  nix_path: nixpkgs=channel:nixos-24.05
  - name: Config Ubuntu - Setup External Tools