[libc++] [test] Silence C++20 deprecation warnings in the MSVC STL
[libc++] [test] Silence C++20 deprecation warnings in the MSVC STL

... when including msvc_stdlib_force_include.hpp.

git-svn-id: 756ef344af921d95d562d9e9f9389127a89a6314@358782 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/libcxx,llvm-mirror/libcxx,llvm-mirror/libcxx,llvm-mirror/libcxx,llvm-mirror/libcxx