[HOTFIX] Fix uninitialized warning in send_receiver_test.cpp

[LeonhardFS]

Hey, thanks for sharing the code online!

Wanted to try it out, and everything works very smoothly except for a warning that leads to an error given the -Werror setting. Submitting a quick one-liner fix here.

Error log:

.../AnyBlob/test/unit/network/send_receiver_test.cpp: In function ‘void anyblob::network::test::C_A_T_C_H_T_E_S_T_0()’:
.../AnyBlob/test/unit/network/send_receiver_test.cpp:60:37: error: ‘skip’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
   60 |                     REQUIRE(!strncmp(reinterpret_cast<char*>(currentMessage.get()) + skip, reinterpret_cast<char*>(message.getData()) + message.getOffset(), message.getSize()));
      |                                     ^
At global scope:
cc1plus: note: unrecognized command-line option ‘-Wno-unqualified-std-cast-call’ may have been intended to silence earlier diagnostics
cc1plus: all warnings being treated as errors
make[2]: *** [CMakeFiles/tester.dir/build.make:202: CMakeFiles/tester.dir/test/unit/network/send_receiver_test.cpp.o] Error 1
make[2]: *** Waiting for unfinished jobs....
make[1]: *** [CMakeFiles/Makefile2:113: CMakeFiles/tester.dir/all] Error 2
make[1]: *** Waiting for unfinished jobs....

My platform:

Ubuntu 22.04.03
CMake 3.22.1 (also tried with 3.31)
GCC 11.4

Let me know if this acceptable or you'd like me to make additional changes!