`overlays.utils` is out of date

[HeinrichApfelmus]

The overlays.utils attribute of the flake.nix file cannot be used — it throws various errors on usage.

Specifically,

iohk-nix/overlays/utils/default.nix

Line 2 in d407eed

inherit (final) system git nixFlakes cabal writeShellScriptBin;

references an attribute nixFlakes of nixpkgs, which now throws an error as of 2024-10-17.

https://github.com/NixOS/nixpkgs/blob/058ea3f007e1405c9119954f0fbb67c96ae0a9c2/pkgs/top-level/aliases.nix#L839

[johnalotoski]

Closed by #594