bug in jinja2 join

[Eternity714]

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Dify version

0.8.3

Cloud or Self Hosted

Self Hosted (Docker)

Steps to reproduce

1. use template node
2. add input var arg1 as Array[String]
3. set code as "{{ arg1|join('\n') }}"
4. set arg1 as [ "123", "456", "789" ]
5. run node

✔️ Expected Behavior

output arg1 value with \n, example is 123\n456\n789

❌ Actual Behavior

error: operation not permitted