add react native alias (#32706)

Author: rtrieu

content/en/real_user_monitoring/application_monitoring/react_native/setup/reactnative.md

@@ -9,6 +9,7 @@ aliases:
     - /real_user_monitoring/reactnative/
     - /real_user_monitoring/mobile_and_tv_monitoring/setup/reactnative
     - /real_user_monitoring/mobile_and_tv_monitoring/react_native/setup
+    - /real_user_monitoring/mobile_and_tv_monitoring/react_native/setup/reactnative/
 further_reading:
 - link: /real_user_monitoring/application_monitoring/react_native/advanced_configuration
   tag: Documentation