k9s: fix build on darwin

pkgs/applications/networking/cluster/k9s/default.nix

@@ -1,4 +1,4 @@
-{ stdenv, buildGoModule, fetchFromGitHub }:
+{ stdenv, buildGoModule, fetchFromGitHub, Security }:
 
 buildGoModule rec {
   pname = "k9s";
@@ -22,6 +22,8 @@ buildGoModule rec {
 
   modSha256 = "06m4xgl29zx6zpqx630m9cm52wmljms9cvly5f4pqdb4zicq7n86";
 
+  buildInputs = stdenv.lib.optionals stdenv.isDarwin [ Security ];
+
   meta = with stdenv.lib; {
     description = "Kubernetes CLI To Manage Your Clusters In Style.";
     homepage = "https://github.com/derailed/k9s";