Update cachix/install-nix-action action to v27

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
cachix/install-nix-action	action	major	v22 -> v27
cachix/install-nix-action	action	major	v25 -> v27

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Release Notes

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

### [`v27`](https://togithub.com/cachix/install-nix-action/releases/tag/v27) [Compare Source](https://togithub.com/cachix/install-nix-action/compare/v26...v27) ##### What's Changed - Enable `always-allow-substitutes` by default by [@​sandydoo](https://togithub.com/sandydoo) in [https://github.com/cachix/install-nix-action/pull/207](https://togithub.com/cachix/install-nix-action/pull/207) - nix: 2.20.5 -> 2.22.1 by [@​kashw2](https://togithub.com/kashw2) in [https://github.com/cachix/install-nix-action/pull/206](https://togithub.com/cachix/install-nix-action/pull/206) - ci: fix tests by [@​sandydoo](https://togithub.com/sandydoo) in [https://github.com/cachix/install-nix-action/pull/208](https://togithub.com/cachix/install-nix-action/pull/208) ##### New Contributors - [@​kashw2](https://togithub.com/kashw2) made their first contribution in [https://github.com/cachix/install-nix-action/pull/206](https://togithub.com/cachix/install-nix-action/pull/206) **Full Changelog**: https://github.com/cachix/install-nix-action/compare/v26...V27 ### [`v26`](https://togithub.com/cachix/install-nix-action/releases/tag/v26) [Compare Source](https://togithub.com/cachix/install-nix-action/compare/v25...v26) Bump to Nix 2.20.5 to address CVE-2024-27297 / GHSA-2ffj-w4mj-pg37. ### [`v25`](https://togithub.com/cachix/install-nix-action/releases/tag/v25): install-nix-action-v25 [Compare Source](https://togithub.com/cachix/install-nix-action/compare/v24...v25) Nix 2.19.2 ### [`v24`](https://togithub.com/cachix/install-nix-action/releases/tag/v24): install-nix-action-v24 [Compare Source](https://togithub.com/cachix/install-nix-action/compare/v23...v24) - Nix 2.19.1 - enables KVM on linux - set `TMPDIR` to avoid potential disk space issues - don't use the default GitHub token for Enterprise ### [`v23`](https://togithub.com/cachix/install-nix-action/releases/tag/v23): install-nix-action-v23 [Compare Source](https://togithub.com/cachix/install-nix-action/compare/v22...v23) - always show Nix trace - Nix 2.17

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