message: Fix cli argument parsing of help option
  Fixes
diff: @@ -453,7 +453,7 @@ std::string actor_system_config::render_exit_reason(uint8_t x, atom_value,
  void actor_system_config::extract_config_file_path(message& args) {
  auto res = args.extract_opts({
  {"caf#config-file", "", config_file_path}
  - });
  + }, nullptr, true);
  args = res.remainder;
  }
  