chore(deps): update determinatesystems/nix-installer-action action to v7

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
DeterminateSystems/nix-installer-action	action	major	v6 -> v7

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Release Notes

DeterminateSystems/nix-installer-action (DeterminateSystems/nix-installer-action)

### [`v7`](https://togithub.com/DeterminateSystems/nix-installer-action/compare/v6...v7) [Compare Source](https://togithub.com/DeterminateSystems/nix-installer-action/compare/v6...v7)

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Configuration

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