Workflow execution failure: node schema's Configs should implement BranchBuilder, node type= Plugin

在 coze-studio 工作流里，创建一个循环节点，里面只引用一个plugin 节点，然后试运行这个循环节点，就报错了：Workflow execution failure: node schema's Configs should implement BranchBuilder, node type= Plugin

这个是怎么回事？我试了试coze.cn 这样是可以的

Reproduce the failure in a workflow containing a loop node with one plugin node, then trace the execution path for the plugin configuration from the reported BranchBuilder error. Compare the behavior with the working coze.cn example; done means the loop executes successfully without this error.

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