[Docs] Fix typo in `restful_api ` user guide (#858)

fix ".generate" to ".chat_interactive_v1"

docs/zh_cn/restful_api.md

@@ -56,7 +56,7 @@ LMDeploy 的 `/v1/chat/interactive` api 支持将对话内容管理在服务端
 ```python
 from lmdeploy.serve.openai.api_client import APIClient
 api_client = APIClient('http://{server_ip}:{server_port}')
-for item in api_client.generate(prompt='hi'):
+for item in api_client.chat_interactive_v1(prompt='hi'):
     print(item)
 ```