Demo: author api

### Expected Behavior
With https://github.com/AElfProject/backend-templates.
Demo with author api.

### Specifications
-

**Features:**
-

**Development Tasks:**
- [ ] API call demo 
- [ ] Task 2

### Dependencies
List any dependencies that are required for this feature by providing links to the issues or repositories.

### References
List any references that are related to this feature request.