donpapi: mark as broken on darwin

pkgs/by-name/do/donpapi/package.nix

···
 {
   lib,
+  stdenv,
   python3,
   fetchFromGitHub,
 }:
···
     license = licenses.gpl3Only;
     maintainers = with maintainers; [ fab ];
     mainProgram = "donpapi";
+    broken = stdenv.hostPlatform.isDarwin;
   };
 }