gem-config: add zookeeper (#44100)

Changed files
+4
pkgs
development
ruby-modules
gem-config
+4
pkgs/development/ruby-modules/gem-config/default.nix
···
'';
};
+
zookeeper = attrs: {
+
buildInputs = stdenv.lib.optionals stdenv.isDarwin [ darwin.cctools ];
+
};
+
}