python3Packages.flatten-dict: fix version in pyproject.toml

pkgs/development/python-modules/flatten-dict/default.nix

@@ -3,6 +3,7 @@
   buildPythonPackage,
   fetchFromGitHub,
   poetry-core,
+  pyprojectVersionPatchHook,
   pytestCheckHook,
 }:
 
@@ -20,6 +21,10 @@ buildPythonPackage (finalAttrs: {
 
   build-system = [ poetry-core ];
 
+  nativeBuildInputs = [
+    pyprojectVersionPatchHook
+  ];
+
   nativeCheckInputs = [ pytestCheckHook ];
 
   pythonImportsCheck = [ "flatten_dict" ];