Remove extra arm CI hack

Author: vinay-deshmukh

libcxx/include/__tree

@@ -618,15 +618,7 @@ public:
     allocator_traits<_Alloc>::construct(__na, std::addressof(__get_value()), std::forward<_Args>(__args)...);
   }
 
-// TODO: workaround for arm CI which uses clang-19.1.4
-/*
-note: non-literal type 'std::__tree_node<std::__value_type<int, int>, void *>' cannot be used in a constant expression
-*/
-#if _LIBCPP_STD_VER >= 26
-  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX26 ~__tree_node() {}
-#else
   ~__tree_node()                             = delete;
-#endif
   __tree_node(__tree_node const&)            = delete;
   __tree_node& operator=(__tree_node const&) = delete;
 };