fix(test): use __SANITIZE_ADDRESS__ alone for sanitizer detection (gcc-portable)

GCC's preprocessor doesn't short-circuit 'defined(__has_feature) && __has_feature(...)' — it tries to parse the call syntax of the undefined token and errors with 'missing binary operator before token "("'. Modern GCC and Clang both define __SANITIZE_ADDRESS__ under -fsanitize=address, so use that single check.