/// <summary>
 /// 拼接当前流程至已存在流程后
 /// </summary>
 /// <param name="newFlowEngine">新流程</param>
 /// <param name="oldFlowEngine">old流程</param>
 public static void Concat(FlowEngine newFlowEngine, FlowEngine oldFlowEngine)
 {
     foreach (var step in newFlowEngine.FlowSteps)
     {
         oldFlowEngine.Add(step);
     }
 }