update OWNERS for vts related projects

Bug: none
Test: none
Change-Id: I91c234f3d8ba93f4120efff0dfed7954c2b24bc5
diff --git a/OWNERS b/OWNERS
index 4d9907d..de4c089 100644
--- a/OWNERS
+++ b/OWNERS
@@ -1 +1,2 @@
 yim@google.com
+guangzhu@google.com