### What problem does this PR solve?
Add test for document
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
Co-authored-by: liuhua <10215101452@stu.ecun.edu.cn>
### What problem does this PR solve?
API: Adds the feature of uploading document.
### Type of change
- [x] New Feature (non-breaking change which adds functionality)