Add a command that will freeze clickhouse-server process with STOP signal and wakeup it after specified amount of time.
This is needed for testing (fault injection).

Wakeup can be done with `ShellCommand` running `sleep N && kill -CONT pid`
else
                    return false;
            }
            res->storage_policy = storage_policy_str;
            res->volume = volume_str;
            if (res->volume.empty() && res->storage_policy.empty())
                parseDatabaseAndTableName(pos, expected, res->database, res->table);
            break;
        }
        case Type::STOP_TTL_MERGES:
        case Type::START_TTL_MERGES:
        case Type::STOP_MOVES:
        case Type::START_MOVES:
        case Type::STOP_FETCHES:
        case Type::START_FETCHES:
        case Type::STOP_REPLICATED_SENDS:
        case Type::START_REPLICATED_SENDS:
        case Type::STOP_REPLICATION_QUEUES:
        case Type::START_REPLICATION_QUEUES:
            parseDatabaseAndTableName(pos, expected, res->database, res->table);
            break;
        default:
            
            break;
    }
    node = std::move(res);
    return true;
}
}