ArduinoOTA: don't crash on unrecognized packets (#4086)
ArduinoOTA: don't crash on unrecognized packets (#4086)

* ArduinoOTA: handle end of packet in readStringUntil

fixes #3912

* ArduinoOTA: fix buffer overflow in parseInt

fixes #3912

wemos/Arduino,Lan-Hekary/Arduino,hallard/Arduino,Adam5Wu/Arduino,esp8266/Arduino,lrmoreno007/Arduino,sticilface/Arduino,Adam5Wu/Arduino,Lan-Hekary/Arduino,hallard/Arduino,lrmoreno007/Arduino,esp8266/Arduino,Adam5Wu/Arduino,sticilface/Arduino,Adam5Wu/Arduino,lrmoreno007/Arduino,Lan-Hekary/Arduino,hallard/Arduino,esp8266/Arduino,sticilface/Arduino,hallard/Arduino,wemos/Arduino,esp8266/Arduino,lrmoreno007/Arduino,lrmoreno007/Arduino,wemos/Arduino,Lan-Hekary/Arduino,hallard/Arduino,Adam5Wu/Arduino,sticilface/Arduino,esp8266/Arduino,sticilface/Arduino,wemos/Arduino,wemos/Arduino,Lan-Hekary/Arduino