Use flake-utils from numtide

Author: andreabedini

flake.lock

@@ -8,7 +8,7 @@
     haskell-nix.inputs.hackage.follows = "hackage-nix";
     hackage-nix.url = "github:input-output-hk/hackage.nix";
     hackage-nix.flake = false;
-    flake-utils.follows = "haskell-nix/flake-utils";
+    flake-utils.url = "github:numtide/flake-utils";
   };
 
   outputs = { nixpkgs, flake-utils, haskell-nix, ... }: