[scudo/standalone] Fix leak in ThreadedGlobalQuarantine test

This unit test code was using malloc without a corresponding free.
When the system malloc is not being overridden by the code under
test, it might an asan/lsan allocator that notices leaks.

Reviewed By: phosek

Differential Revision: https://reviews.llvm.org/D91472

GitOrigin-RevId: 6ef07111a402a87fda096b6b8d7327e4aa89d4d6
1 file changed