v1.5.1 to fix String-related bug

### Releases v1.5.1

1. Fix bug related to String in library and examples

Author: khoih-prog

README.md

@@ -2009,7 +2009,9 @@ The following are debug terminal output and screen shot when running example [**
 Starting AdvancedServer on PORTENTA_H7_M7 with Portenta_H7 WiFi
 WiFiWebServer v1.5.1
 Connecting to WPA SSID: HueNet1
-HTTP server started @ 192.168.2.130
+HTTP server started @ 192.168.2.138
+H[WIFI] String Len = 0, extend to 2048
+HHHHHHHHH HHHHHHH
 ```
 
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