fix setCaptivePortalEnable

examples/OnDemandConfigPortal/OnDemandConfigPortal.ino

@@ -42,6 +42,8 @@ void loop() {
     //WITHOUT THIS THE AP DOES NOT SEEM TO WORK PROPERLY WITH SDK 1.5 , update to at least 1.5.1
     //WiFi.mode(WIFI_STA);
     
+    wifiManager.setCaptivePortalEnable(false);
+    
     if (!wifiManager.startConfigPortal("OnDemandAP")) {
       Serial.println("failed to connect and hit timeout");
       delay(3000);