stabber: fix darwin build

pkgs/misc/stabber/default.nix

···
 { lib, stdenv, fetchFromGitHub, autoreconfHook, pkg-config, glib, expat
-, libmicrohttpd
+, libmicrohttpd, darwin
 }:
 
 with lib;
···
   '';
 
   nativeBuildInputs = [ pkg-config autoreconfHook ];
-  buildInputs = [ glib expat libmicrohttpd ];
+  buildInputs = [ glib expat libmicrohttpd ] ++
+    lib.optionals stdenv.isDarwin [ darwin.apple_sdk.frameworks.Security ];
 
   meta = {
     description = "Stubbed XMPP Server";