In dify1.15.0 version, when two Human Input nodes are used, the output content is abnormal

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### Dify version

1.15.0

### Cloud or Self Hosted

Self Hosted (Docker)

### Steps to reproduce

I am deploying in an offline docker compose environment, when upgrading the version from dify 1.10.1-fix.1 to 1.15.0,when two Human Input nodes are used, the output content is abnormal?

The Answer node seems to have output content, but it is not displayed on the UI interface:

### ✔️ Expected Behavior

It displays normally on the UI interface

### ❌ Actual Behavior

The Answer node seems to have output content, but it is not displayed on the UI interface:

Start by reproducing the issue in the self-hosted Docker Compose deployment on Dify 1.15.0, using two Human Input nodes and checking the Answer node output. Trace why the output is present but not displayed in the UI; done means the Answer content displays normally after the upgrade.

Written by the indexing model from the issue text.