[release-24.05] nix: fix macOS sandbox escape via builtin builders

[Mic92]

fixes
GHSA-wf4c-57rh-9pjg

Backport of #352455

(cherry picked from commit 2f6dc5c)

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandboxing enabled in nix.conf? (See Nix manual)
  • sandbox = relaxed
  • sandbox = true
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 24.11 Release Notes (or backporting 23.11 and 24.05 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
• Fits CONTRIBUTING.md.

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[emilazy]

Building on aarch64-linux. (actually the non‐backport)

[Mic92]

@emilazy ofborg is running this already btw. So both x86/arm64 already work.

[emilazy]

The Nix builds for nixpkgs-24.05-darwin have finished, so the fallback paths for those could be updated.