message: Avoid accessing static value through object
diff: @@ -98,14 +98,14 @@ public:
  switch (static_cast<uint64_t>(msg.get_as<atom_value>(0))) {
  default:
  break;
  - case link_atom::value.uint_value(): {
  + case link_atom::uint_value(): {
  if (ptr != nullptr)
  static_cast<actor_proxy*>(ptr->get())->add_link(dst->get());
  else
  CAF_LOG_WARNING("received link message with invalid target");
  return;
  }
  - case unlink_atom::value.uint_value(): {
  + case unlink_atom::uint_value(): {
  if (ptr != nullptr)
  static_cast<actor_proxy*>(ptr->get())->remove_link(dst->get());
  else
  