need multiple branch supported

[akan]

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1. Is this request related to a challenge you're experiencing? Tell me about your story.

Sometimes I don't need the second classify node instead of a simple node with multiple branch nodes following, then I simplely merge the result, that's what I want. Maybe Iterator node is similar to the solution, but it is not the same.

2. Additional context or comments

the workflow graph need to handle the situation like that: multiple steps with no order index, then merge the results 希望工作流可以处理这种一个节点后，有多个相似的步骤都需要处理，结果还要汇总的。这个地方总分总应该是最清晰的。循环或者串行都不太符合期望的结构。虽然估计也能做。

3. Can you help us with this feature?

• [X] I am interested in contributing to this feature.

[crazywoola]

We are working on parallel feature.