Test adjustment for recent changes in allocator_traits

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@121503 91177308-0d34-0410-b5e6-96231b3b80d8

test/utilities/allocator.adaptor/types.pass.cpp

@@ -43,7 +43,7 @@ int main()
 
     static_assert((std::is_same<
         std::scoped_allocator_adaptor<A1<int>>::size_type,
-        std::size_t>::value), "");
+        std::make_unsigned<std::ptrdiff_t>::type>::value), "");
 
     static_assert((std::is_same<
         std::scoped_allocator_adaptor<A1<int>>::difference_type,