Add submission # 2341

#2341

Author: ArduinoBot

registry.txt

@@ -5599,3 +5599,4 @@ https://github.com/107-systems/107-Arduino-CriticalSection.git|Contributed|107-A
 https://github.com/uldara1/Modbus.git|Contributed|Modbus
 https://github.com/SyntaxHarvy/HaCEspSockets.git|Contributed|HaCEspSockets
 https://github.com/nkaaf/Arduino-Regression.git|Contributed|Regression
+https://github.com/RobTillaart/MHZCO2.git|Contributed|MHZCO2