message: Support "action" command (it's the same as assert_return without result)
diff: @@ -68,7 +68,7 @@ public:
  }
  pass();
  }
  - else if (type == "assert_return")
  + else if (type == "assert_return" || type == "action")
  {
  const auto& action = cmd.at("action");
  const auto action_type = action.at("type").get<std::string>();
  