message: Remove overlooked use of caf::reacts_to
diff: @@ -27,12 +27,12 @@ namespace {
  // check invariants of type system
  using dummy1 = typed_actor<result<void>(int, int), result<double>(double)>;
  -using dummy2 = dummy1::extend<reacts_to<ok_atom>>;
  +using dummy2 = dummy1::extend<result<void>(ok_atom)>;
  static_assert(std::is_convertible<dummy2, dummy1>::value,
  "handle not assignable to narrower definition");
  -using dummy3 = typed_actor<reacts_to<float, int>>;
  +using dummy3 = typed_actor<result<void>(float, int)>;
  using dummy4 = typed_actor<result<double>(int)>;
  using dummy5 = dummy4::extend_with<dummy3>;
  @@ -345,7 +345,7 @@ CAF_TEST(sending_typed_actors_and_down_msg) {
  CAF_TEST(check_signature) {
  using foo_type = typed_actor<result<ok_atom>(put_atom)>;
  using foo_result_type = result<ok_atom>;
  - using bar_type = typed_actor<reacts_to<ok_atom>>;
  + using bar_type = typed_actor<result<void>(ok_atom)>;
  auto foo_action = [](foo_type::pointer ptr) -> foo_type::behavior_type {
  return {
  [=](put_atom) -> foo_result_type {
  