egg-plugin-assets 在开发环境下固定资源路径host为127.0.0.1

## What happens?
A clear and concise description of what the bug is.

https://github.com/eggjs/egg-view-assets/blob/52f2aac23bf34eff576fe2ed1c82a6075874b38b/app.js#L22
这行代码固定了local环境下asset的资源路径为127.0.0.1

做手机页面的时候，需要在手机调试js-sdk功能，这时候的 resourceBase 是127.0.0.1，资源访问不到

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## How To Reproduce

**Steps to reproduce the behavior:**
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**Expected behavior**
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## Context
- **Node Version**:
- **Egg Version**:
- **Plugin Name**:
- **Plugin Version**:
- **Platform**: