[libc-commits] [libc] [libc][test] fix memory leak (PR #122378)

[Nick Desaulniers via libc-commits]

nickdesaulniers wrote:

No; it's probably not too bad to add a `cpp::unique_ptr` to a newly created libc/src/__support/CPP/memory.h, but I'll leave that cleanup for another time when the builds not red.

https://github.com/llvm/llvm-project/pull/122378