temporarily add xiangyan as search codeowner to approve non-spec related changes. (#40132)

Author: xiangyan99

.github/CODEOWNERS

@@ -221,7 +221,7 @@
 /specification/scheduler/ @pinwang81
 
 # PRLabel: %Search
-/specification/search/data-plane/ @kuanlu95 @BevLoh @giulianob
+/specification/search/data-plane/ @kuanlu95 @BevLoh @giulianob @xiangyan99
 
 # PRLabel: %Search
 /specification/search/resource-manager/ @efrainretana @BevLoh @xiong-qiao @jonathanserbent @Draconicida @kuanlu95 @admayber