Update cachix/install-nix-action action to v25 - autoclosed

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
cachix/install-nix-action	action	major	v23 -> v25

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Release Notes

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

### [`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

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Configuration

📅 Schedule: Branch creation - "before 4am on Monday" (UTC), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• [ ] If you want to rebase/retry this PR, check this box

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