ci(tools): update cachix/install-nix-action action to v31

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
cachix/install-nix-action	action	major	v30 -> v31

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Release Notes

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

v31

Compare Source

What's Changed

• nix: 2.24.9 -> 2.25.2 by @​Mic92 in https://github.com/cachix/install-nix-action/pull/218
• ci: fix latest installer tests by @​sandydoo in https://github.com/cachix/install-nix-action/pull/220
• ci: add ubuntu-24.04-arm to matrix by @​msgilligan in https://github.com/cachix/install-nix-action/pull/221
• nix: 2.25.2 -> 2.26.2 by @​Mic92 in https://github.com/cachix/install-nix-action/pull/226

New Contributors

• @​msgilligan made their first contribution in https://github.com/cachix/install-nix-action/pull/221

Full Changelog: cachix/install-nix-action@v30...v31

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Configuration

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🚦 Automerge: Enabled.

♻ Rebasing: Whenever PR is behind base branch, 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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