[Bug libstdc++/99752] ranges::find_end should return empty subrange when search range is empty

[hewillk at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99752

--- Comment #1 from 康桓瑋 <hewillk at gmail dot com> ---
My pardon, since the ranges::find_end return type is ranges::subrange<I1>, we
still to get the common last1 iterator through the ranges::next call, so this
seems not a bug.