[libcxx-commits] [libcxx] [libc++][test] Improves substitution naming (PR #80471)

[Louis Dionne via libcxx-commits]

ldionne wrote:

@StephanTLavavej I think you're not in the libcxx-vendors group but this may impact you slightly. LMK if you want to be added to the group, it's low traffic.

https://github.com/llvm/llvm-project/pull/80471