nix build fix (haskell#3569)

Author: July541

configuration-ghc-96.nix

@@ -42,6 +42,7 @@ let
  ptr-poker = hself.callCabal2nix "ptr-poker" inputs.ptr-poker { };
 
  ormolu = hself.ormolu_0_5_3_0;
+ fourmolu = hself.callCabal2nix "fourmolu" inputs.fourmolu-012 { };
 
  stylish-haskell = appendConfigureFlag hsuper.stylish-haskell "-fghc-lib";
 

flake.lock

@@ -59,6 +59,11 @@
  url = "github:alanz/ghc-exactprint/ghc-9.6";
  flake = false;
  };
+
+ fourmolu-012 = {
+ url = "https://hackage.haskell.org/package/fourmolu-0.12.0.0/fourmolu-0.12.0.0.tar.gz";
+ flake = false;
+ };
  };
  outputs =
  inputs@{ self, nixpkgs, flake-compat, flake-utils, gitignore, ... }: