Recently I've seen the test test_StatusCodeFail fail in the gitlab-ci jobs because it triggers a recompilation of GaudiKernel. In principle it should not happen as GaudiKernel should be already available, OTOH there is no need to build it to just try to compile one source file.
This MR changes the test so that it only compile the source file instead of trying to build the executable.
I also split the test in 4 sub-tests, as at some point I had problems with Clang not showing all errors.
See #177