[IDE] migrate test folder to CMake configuration

[Arpafaucon]

As discussed via discord, here's a proposed PR to migrate test.

Some notes

• I kept DEBUGINFOD enabled by default on linux platforms like in the MakeFile
• we "include" the top-level CmakeLists.txt to get the TracyClient target - that's a bit unorthodox but seems to work well
• on my Ubuntu machine, I don't need to link explicitly against pthread but IIRC some other Linux need it, so I kept it explicit for everyone
• -ldl link option seems implicitly added by CMake, so I don't mention it explictly
• updated std= option from gnu++11 to gnu++20 to align with other projects
• due to the way CMake works, the -Wall -g3 -fmerge-constants options are not propagated anymore to TracyClient.cpp (because it's a different library) - people will have to add them explicitly for debugging if needed.

For comparison, here are the new compilation lines (I had disabled DEBUGINFOD for this run)

/usr/bin/c++ -DTRACY_ENABLE -isystem /home/gregoire.roussel/dev/perf/tracy/public -std=gnu++20 -MD -MT client/CMakeFiles/TracyClient.dir/public/TracyClient.cpp.o -MF CMakeFiles/TracyClient.dir/public/TracyClient.cpp.o.d -o CMakeFiles/TracyClient.dir/public/TracyClient.cpp.o -c /home/gregoire.roussel/dev/perf/tracy/public/TracyClient.cpp
/usr/bin/c++ -DTRACY_ENABLE -isystem /home/gregoire.roussel/dev/perf/tracy/public -Wall -g3 -fmerge-constants -std=gnu++20 -MD -MT CMakeFiles/tracy-test.dir/test.cpp.o -MF CMakeFiles/tracy-test.dir/test.cpp.o.d -o CMakeFiles/tracy-test.dir/test.cpp.o -c /home/gregoire.roussel/dev/perf/tracy/test/test.cpp
/usr/bin/c++ -rdynamic CMakeFiles/tracy-test.dir/test.cpp.o -o tracy-test  client/libTracyClient.a -lpthread -ldl

and the compilation lines of the makefile on master

g++ -c -I../public/tracy -g3 -fmerge-constants -Wall -DTRACY_ENABLE -std=gnu++11  test.cpp -o test.o
g++ -c -I../public/tracy -g3 -fmerge-constants -Wall -DTRACY_ENABLE -std=gnu++11  ../public/TracyClient.cpp -o ../public/TracyClient.o
g++ -g3 -fmerge-constants -Wall -DTRACY_ENABLE -std=gnu++11  test.o ../public/TracyClient.o -lpthread -ldl -rdynamic -o tracy_test

Additional changes

I also added a safeguard around the use of the image to detect when the loading failed. It took me some time to understand I was not running the executable from the right location; I hope error lines will help the next dev :)

[Arpafaucon]

Like always, I forgot about the CI configuration. I updated it for CMake, and I had to add the advanced option TRACY_DEMANGLE to match the existing test