Update cachix/install-nix-action action to v30

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
cachix/install-nix-action	action	major	v29 -> v30

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Release Notes

cachix/install-nix-action (cachix/install-nix-action)

### [`v30`](https://redirect.github.com/cachix/install-nix-action/releases/tag/v30) [Compare Source](https://redirect.github.com/cachix/install-nix-action/compare/v29...v30) - Nix: 2.24.7 -> 2.24.9, fixing [GHSA-6fjr-mq49-mm2c](https://redirect.github.com/NixOS/nix/security/advisories/GHSA-6fjr-mq49-mm2c)

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Configuration

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