doc: Add fhinkel to collaborators

Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
PR-URL: #8052

Author: fhinkel

README.md

@@ -216,6 +216,8 @@ more information about the governance of the Node.js project, see
 **Robert Jefe Lindstaedt** <robert.lindstaedt@gmail.com>
 * [estliberitas](https://github.com/estliberitas) -
 **Alexander Makarenko** <estliberitas@gmail.com>
+* [fhinkel](https://github.com/fhinkel) -
+**Franziska Hinkelmann** <franziska.hinkelmann@gmail.com>
 * [firedfox](https://github.com/firedfox) -
 **Daniel Wang** <wangyang0123@gmail.com>
 * [geek](https://github.com/geek) -