chore(deps): update determinatesystems/magic-nix-cache-action action to v4

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
DeterminateSystems/magic-nix-cache-action	action	major	v3 -> v4

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Release Notes

DeterminateSystems/magic-nix-cache-action (DeterminateSystems/magic-nix-cache-action)

### [`v4`](https://togithub.com/DeterminateSystems/magic-nix-cache-action/compare/v3...v4) [Compare Source](https://togithub.com/DeterminateSystems/magic-nix-cache-action/compare/v3...v4)

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Configuration

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

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