API based plugin get null input but the variable is not null

[forrestsocool]

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Dify version

0.6.12

Cloud or Self Hosted

Cloud

Steps to reproduce

api based plugin in the workflow, the input "article_ids" is not null, but server recieve null.

✔️ Expected Behavior

plugin should post it's input, regardless of it's special character or something, it's user's stuff.

❌ Actual Behavior

server recieve null