Fix UE5.3 Linux Compile

[morotsgurka]

Fix for pointer error
Took the implementation from the Windows StringUtils.cpp which seems to work fine

[tustanivsky]

@morotsgurka Thank you, this is much appreciated!

[morotsgurka]

No problem!

The same seems to have to be done on the MacOS StringUtils like Toernblom wrote in my issue #33
I think that it is the same issue as issue #37. My guess is that Mosquitto is built for Intel and has to be rebuilt for ARM to work on M1? Although, I am not able to compile Mosquitto from source, I get an error which i have not been able to solve.

clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [lib/libmosquitto.2.0.18.dylib] Error 1
make[1]: *** [lib/CMakeFiles/libmosquitto.dir/all] Error 2
make: *** [all] Error 2

Found this issue and solution on Mosquittos repo but it did not seem to work for me.