simplify type_trait

Author: vinay-deshmukh

libcxx/include/__tree

@@ -1058,7 +1058,7 @@ public:
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX26 void
   __insert_unique_from_orphaned_node(const_iterator __p, __get_node_value_type_t<_Tp>&& __value) {
 #if _LIBCPP_STD_VER >= 26
-    if constexpr (integral_constant<bool, is_copy_constructible<decltype(__value.first)>::value >()) {
+    if constexpr (std::is_copy_constructible_v<decltype(__value.first)>) {
       __emplace_hint_unique(__p, std::move(__value.first), std::move(__value.second));
     } else
 #endif
@@ -1344,7 +1344,7 @@ private:
 
 #if _LIBCPP_STD_VER >= 26
 
-    if constexpr (integral_constant<bool, is_copy_constructible<decltype(__rhs.first)>::value >()) {
+    if constexpr (std::is_copy_constructible_v<decltype(__rhs.first)>) {
       // we use copy, and not "move" as the constraint
       // because we can NOT move from `const key_type`, which is how `value_type` is defined
       // atleast for map