Fix Linking Error Caused by Protobuf

[Zi7ar21]

Whenever I attempt to run make, it fails because ld can't find "_ZN4absl12lts_2023080212log_internal17MakeCheckOpStringIllEEPNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEET_T0_PKc":

[jacob@jacobarch build]$ make
[  0%] Built target gnss-sdr-monitor_autogen_timestamp_deps
[  4%] Built target gnss-sdr-monitor_autogen
[  8%] Linking CXX executable gnss-sdr-monitor
/usr/bin/ld: CMakeFiles/gnss-sdr-monitor.dir/channel_table_model.cpp.o: undefined reference to symbol '_ZN4absl12lts_2023080212log_internal17MakeCheckOpStringIllEEPNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEET_T0_PKc'
/usr/bin/ld: /usr/lib/libabsl_log_internal_check_op.so.2308.0.0: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status
make[2]: *** [src/CMakeFiles/gnss-sdr-monitor.dir/build.make:420: src/gnss-sdr-monitor] Error 1
make[1]: *** [CMakeFiles/Makefile2:101: src/CMakeFiles/gnss-sdr-monitor.dir/all] Error 2
make: *** [Makefile:136: all] Error 2
[jacob@jacobarch build]$

This can be fixed by implementing the changes found here: https://stackoverflow.com/a/77151107

Basically, changing:

find_package(Protobuf REQUIRED)

in CMakeLists.txt to:

find_package(Protobuf REQUIRED CONFIG)

which causes CMake to say:

Unknown CMake command "protobuf_generate_cpp"

but it's OK because you can make it shut up by adding -Dprotobuf_MODULE_COMPATIBLE:BOOL=ON when you run cmake (I added the updated CMake command to the README).

[Zi7ar21]

@acebrianjuan