[libcxx-commits] [libcxx] [libc++]Update Libcxx ranges::contains_subrange() status (PR #81816)

[Hristo Hristov via libcxx-commits]

H-G-Hristov wrote:

@ZijunZhaoCCK I'd rename the title to `[libc++][ranges] Set feature test macro `__cpp_lib_ranges_contains` and `__cpp_lib_ranges_starts_ends_with` and also add links to the commits implementing the papers to the commit message (PR description above) for the record.
Otherwise it LGTM. Please wait for someone else to approve. Maybe @var-const 

https://github.com/llvm/llvm-project/pull/81816