sanitizer: Fix -Wpedantic GCC warning

Fixes:
sanitizer_stacktrace.h:212:5: warning: ISO C++ forbids braced-groups within expressions [-Wpedantic]

Differential Revision: https://reviews.llvm.org/D113292

GitOrigin-RevId: 78d3e0a4f1406b17cdecc77540e09210670fe9a9
1 file changed