chore(deps): update cachix/install-nix-action action to v19

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
cachix/install-nix-action	action	major	v18 -> v19

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Release Notes

cachix/install-nix-action

### [`v19`](https://togithub.com/cachix/install-nix-action/releases/tag/v19): install-nix-action-v19 [Compare Source](https://togithub.com/cachix/install-nix-action/compare/v18...v19) - expose github_access_token option and use the default github token by default to prevent rate limiting - support `--no-daemon` installation

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Configuration

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[what-the-diff[bot]]

• Update the version of cachix/install-nix-action from v18 to v19