Minor: fixed broken links. (#8636)

### What problem does this PR solve?



### Type of change

- [x] Documentation Update

docs/references/http_api_reference.md

 
 This operation requires a `Bearer Login Token`, which typically expires with in 24 hours. You can find the it in the Request Headers in your browser easily as shown below:
 
-![Image](https://github.com/user-attachments/assets/17a5a0fe-e411-4e35-8251-85c71444468b)
+![Image](https://raw.githubusercontent.com/infiniflow/ragflow-docs/main/images/login_token.jpg)
 
 :::tip NOTE
 The chat model autonomously determines the number of questions to generate based on the instruction, typically between five and ten.