Fix for missing enum in hpu_model_runner.py

Author: michalkuligowski

vllm/worker/hpu_model_runner.py

@@ -15,7 +15,7 @@
 import os
 import time
 from array import array
-from enum import IntEnum
+from enum import Enum, IntEnum
 from typing import (TYPE_CHECKING, Any, Callable, Dict, List, NamedTuple,
                     Optional, Set, Tuple, Type, TypeVar, Union)