Add submission # 5261

#5261

Author: ArduinoBot

registry.txt

@@ -7518,3 +7518,4 @@ https://github.com/smelpro/Smelpro_Macaron.git|Contributed|Smelpro Macaron Libra
 https://github.com/Garfius/cliSerialMenu.git|Contributed|Menu-UI
 https://github.com/ncmreynolds/milesTag.git|Contributed|milesTag
 https://github.com/nhjschulz/cfsm.git|Contributed|CFSM
+https://github.com/bitcode-tech/uart_keyboard.git|Contributed|UART_Keyboard