http Request [Errno -3] Temporary failure in name resolution

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### Dify version

1.16.1

### Cloud or Self Hosted

Self Hosted (Docker)

### Steps to reproduce

After I upgraded from version 1.13.0 to 1.16.1, the HTTP requests in the original workflow threw errors. [Errno -3] Temporary failure in name resolution

I have modified the. env file and added the required content to it.

The IP I requested belongs to a computer on my local area network. It worked fine on version 1.13.0, but this error occurs after the upgrade.

### ✔️ Expected Behavior

Able to send HTTP requests normally, thank you

### ❌ Actual Behavior

_No response_

Start with the self-hosted Docker deployment and compare the .env configuration between versions 1.13.0 and 1.16.1, then reproduce the HTTP request against the local-network IP while checking the reported name-resolution failure. Done means the original workflow can send HTTP requests normally after the upgrade.

Written by the indexing model from the issue text.