[libc++][ranges] export std::ranges::range_adaptor_closure (llvm#89793)

This patch exports the `std::ranges::range_adaptor_closure` class
template implemented in llvm#89148 from the C++ Modules file.

Author: Xiaoyang Liu

libcxx/modules/std/ranges.inc

@@ -138,8 +138,10 @@ export namespace std {
     }
 #endif // _LIBCPP_HAS_NO_LOCALIZATION
 
+#if _LIBCPP_STD_VER >= 23
     // [range.adaptor.object], range adaptor objects
-    // using std::ranges::range_adaptor_closure;
+    using std::ranges::range_adaptor_closure;
+#endif
 
     // [range.all], all view
     namespace views {