[Bug libstdc++/95322] std::list | take | transform, expression does not work cbegin() == end()

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95322

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Adding this to transform_view::_Sentinel fixes it:

          friend constexpr bool
          operator==(const _Iterator<true>& __x, const _Sentinel& __y)
          requires (!_Const)
          { return _Sentinel<true>(__y).__equal(__x); }