[Bug libstdc++/71337] temp_directory_path(error_code&) shouldn't throw from !exists(p) || !is_directory(p)

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71337

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
fixed on trunk so far.