Add comments about Netty communications

hippo4j-example/hippo4j-spring-boot-starter-example/src/main/resources/application.properties

@@ -7,7 +7,8 @@ spring.application.name=dynamic-threadpool-example
 
 spring.dynamic.thread-pool.server-addr=http://localhost:6691
 spring.dynamic.thread-pool.netty-server-port=8899
-spring.dynamic.thread-pool.report-type=netty
+### Use netty to report thread pool monitoring data. The default is http.
+# spring.dynamic.thread-pool.report-type=netty
 spring.dynamic.thread-pool.namespace=prescription
 spring.dynamic.thread-pool.item-id=dynamic-threadpool-example
 spring.dynamic.thread-pool.username=admin