Revert "[libc++] Remove the type_traits includes from limits and new"

type_traits doesn't need to include __type_traits/noexcept_move_assign_container.h, so there is no include cycle from <limits> or <new>. Restore their includes of type_traits to preserve compatibility.

This reverts commit 2af6d79c.

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D154747