delete invalida import

Author: qmkakaxi

vllm_ascend/worker/model_runner_v1.py

@@ -25,7 +25,6 @@
 from contextlib import contextmanager, nullcontext
 from dataclasses import dataclass
 from typing import TYPE_CHECKING, Dict, List, Optional, Union
-from multiprocessing import Manager
 
 import numpy as np
 import numpy.typing as npt