fix: asyncUpdate example

Author: HoustonAsh

examples/AsyncUpdate/AsyncUpdate.ino

@@ -1,8 +1,10 @@
-#include <WiFi.h>
+#include <NTPClient.h>
+// change next line to use with another board/shield
+#include <ESP8266WiFi.h>
+//#include <WiFi.h> // for WiFi shield
+//#include <WiFi101.h> // for WiFi 101 shield or MKR1000
 #include <WiFiUdp.h>
 
-#include "NTPClient.h"
-
 #define SSID "<your-ssid>"
 #define PASSWORD "<your-password>"