`opcua_server.ino` fails to compile with the Modbus MD02 demo

[aliphys]

According to the README.md for the opcua_server.ino sketch, additional flags need to be included in order for the Modbus MD02 example to compile
https://github.com/bcmi-labs/Arduino_open62541/blob/0783872bcb2739652ecafa70a07273271425e244/examples/opcua_server/README.md#L6

The compilation fails, with this message

C:\GitHub\Arduino\Arduino_open62541\examples\opcua_server\opcua_server.ino:53:43: error: 's' does not name a type
 UA_NodeId modbus_md02_temperature_node_id;s
                                           ^

...

Used library           Version Path
Arduino_open62541      0.0.1   C:\GitHub\Arduino\Arduino_open62541
Arduino_Opta_Blueprint 0.2.2   C:\Users\Ali Jahangiri\Documents\Arduino\libraries\Arduino_Opta_Blueprint
Wire                           C:\Users\Ali Jahangiri\AppData\Local\Arduino15\packages\arduino\hardware\mbed_opta\4.1.6\libraries\Wire  
Ethernet               1.0.0   C:\Users\Ali Jahangiri\AppData\Local\Arduino15\packages\arduino\hardware\mbed_opta\4.1.6\libraries\Ethernet
SocketWrapper          1.0     C:\Users\Ali Jahangiri\AppData\Local\Arduino15\packages\arduino\hardware\mbed_opta\4.1.6\libraries\SocketWrapper
ArduinoRS485           1.1.0   C:\Users\Ali Jahangiri\Documents\Arduino\libraries\ArduinoRS485
ArduinoModbus          1.0.9   C:\Users\Ali Jahangiri\Documents\Arduino\libraries\ArduinoModbus
Arduino_SerialUpdater  0.0.1   C:\Users\Ali Jahangiri\Documents\Arduino\libraries\Arduino_SerialUpdater
Arduino_DebugUtils     1.4.0   C:\Users\Ali Jahangiri\Documents\Arduino\libraries\Arduino_DebugUtils

Used platform     Version Path
arduino:mbed_opta 4.1.6   C:\Users\Ali Jahangiri\AppData\Local\Arduino15\packages\arduino\hardware\mbed_opta\4.1.6
Error during build: exit status 1

Looking at the line in question

https://github.com/bcmi-labs/Arduino_open62541/blob/0783872bcb2739652ecafa70a07273271425e244/examples/opcua_server/opcua_server.ino#L52-L54

We see that the additional s ad the end of line 53 is skipped when --build-property compiler.cpp.extra_flags="-DUSE_MODBUS_SENSOR_MD02=1" is not passed to arduino-cli.