message: compare linked pk instead of object key in test
diff: @@ -1630,10 +1630,20 @@ TEST_CASE("app: mixed lists with object links", "[sync][app]") {
  auto list = util::any_cast<List&&>(obj.get_property_value<std::any>(c, "mixed_array"));
  for (size_t idx = 0; idx < list.size(); ++idx) {
  Mixed mixed = list.get_any(idx);
  + if (idx == 3) {
  + CHECK(mixed.is_type(type_TypedLink));
  + auto link = mixed.get<ObjLink>();
  + auto link_table = realm->read_group().get_table(link.get_table_key());
  + CHECK(link_table->get_name() == "class_Target");
  + auto link_obj = link_table->get_object(link.get_obj_key());
  + CHECK(link_obj.get_primary_key() == target_id);
  + }
  + else {
  CHECK(mixed == util::any_cast<Mixed>(mixed_list_values[idx]));
  }
  }
  }
  +}
  TEST_CASE("app: roundtrip values", "[sync][app]") {
  std::string base_url = get_base_url();
  