Update Serial documentation for additional boards

[cattledogGH]

https://www.arduino.cc/reference/en/language/functions/communication/serial/

1. Document the NanoEvery Serial1 on pins 0 and 1 (tx, rx)

2. Document the Nano 33 BLE and BLE Sense Serial1 on pins tx and rx.
   https://docs.arduino.cc/hardware/nano-33-ble
   Document the possibility of an second hardware serial port per
   https://github.com/arduino/ArduinoCore-nRF528x-mbedos/issues/38

UART mySerial(digitalPinToPinName(4), digitalPinToPinName(3), NC, NC);
//(change 4 and 3 as you prefer, the processor can mux any functionality on any pin)
//Note: the order of pins in the constructor is Tx, Rx, and is reversed from other Arduino serial/software serial constructors.