macOS/GCC Debug builds fail in CI due to use of ASAN.

[dabrahams]

2024-08-05T23:33:33.9253730Z : && /usr/local/bin/g++-11 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=3 -fstack-protector-strong -fcf-protection -fstack-clash-protection  -D_GLIBCXX_ASSERTIONS -g -flto=auto -isysroot /Applications/Xcode_15.2.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX14.2.sdk -Wl,-search_paths_first -Wl,-headerpad_max_install_names -fsanitize=address,undefined test/CMakeFiles/abort_is_detected.dir/Debug/abort_is_detected.cpp.o test/CMakeFiles/abort_is_detected.dir/Debug/abort_detection.cpp.o -o test/Debug/abort_is_detected  --coverage && :
2024-08-05T23:33:34.0250750Z -macosx_version_min has been renamed to -macos_version_min
2024-08-05T23:33:34.1096740Z ld: library 'asan' not found
2024-08-05T23:33:34.2098940Z collect2: error: ld returned 1 exit status