bugfix: fix the bug that stream generate not work (#2756)

vllm/entrypoints/api_server.py

@@ -66,7 +66,7 @@ async def generate(request: Request) -> Response:
                 prompt + output.text for output in request_output.outputs
             ]
             ret = {"text": text_outputs}
-            yield (json.dumps(ret) + "\0").encode("utf-8")
+            yield (json.dumps(ret) + "\n").encode("utf-8")
 
     if stream:
         return StreamingResponse(stream_results())