Add Lillian Zhang to main authors

Author: eregon

README.md

@@ -182,7 +182,7 @@ Announcements about GraalVM, including TruffleRuby, are made on the
 The main authors of TruffleRuby ordered by first contribution are:
 Chris Seaton, Benoit Daloze, Kevin Menard, Petr Chalupa, Brandon Fish, Duncan
 MacGregor, Christian Wirth, Rafael França, Alan Wu, Nicolas Laurent, Carol Chen,
-Nikolay Sverchkov.
+Nikolay Sverchkov, Lillian Zhang.
 
 ## Security