doc: add zkat to collaborators

PR-URL: #4142
Reviewed-By: Jeremiah Senkpiel <fishrock123@rocketmail.com>
Reviewed-By: Rebecca Turner <me@re-becca.org>
Reviewed-By: Minwoo Jung <jmwsoft@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: zkat

README.md

@@ -419,6 +419,7 @@ information about the governance of the Node.js project, see
 * [tunniclm](https://github.com/tunniclm) - **Mike Tunnicliffe** <m.j.tunnicliffe@gmail.com>
 * [vkurchatkin](https://github.com/vkurchatkin) - **Vladimir Kurchatkin** <vladimir.kurchatkin@gmail.com>
 * [yosuke-furukawa](https://github.com/yosuke-furukawa) - **Yosuke Furukawa** <yosuke.furukawa@gmail.com>
+* [zkat](https://github.com/zkat) - **Kat Marchán** <kzm@sykosomatic.org>
 
 Collaborators & TSC members follow the [COLLABORATOR_GUIDE.md](./COLLABORATOR_GUIDE.md) in
 maintaining the Node.js project.