message: Fix segfault in blocking actors, close
diff: @@ -119,7 +119,7 @@ void blocking_actor::launch(execution_unit*, bool, bool hide) {
  # endif
  self->cleanup(std::move(rsn), self->context());
  ptr->home_system->dec_detached_threads();
  - }, ctrl()).detach();
  + }, strong_actor_ptr{ctrl()}).detach();
  }
  blocking_actor::receive_while_helper
  