libstdc++: Implement range_adaptor_closure from P2387R3 [PR108827]
PR libstdc++/108827
libstdc++-v3/ChangeLog:
* include/bits/ranges_cmp.h (__cpp_lib_ranges): Bump value
for C++23.
* include/std/ranges (range_adaptor_closure): Define for C++23.
* include/std/version (__cpp_lib_ranges): Bump value for
C++23.
* testsuite/std/ranges/version_c++23.cc: Bump expected value
of __cpp_lib_ranges.
* testsuite/std/ranges/range_adaptor_closure.cc: New test.
(cherry picked from commit
cb5c71d16d0fb47638498365f5c857ce7c673eaf)