[Misc] Replace Optional[X] with X | None syntax (#33332)

Signed-off-by: carlory <baofa.fan@daocloud.io>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

vllm/model_executor/layers/quantization/gptq_marlin.py

@@ -2,7 +2,7 @@
 # SPDX-FileCopyrightText: Copyright contributors to the vLLM project
 
 from copy import deepcopy
-from typing import Any, Optional
+from typing import Any
 
 import torch
 from safetensors.torch import _TYPES as _SAFETENSORS_TO_TORCH_DTYPE
@@ -240,7 +240,7 @@ class GPTQMarlinConfig(QuantizationConfig):
 
     def get_quant_method(
         self, layer: torch.nn.Module, prefix: str
-    ) -> Optional["QuantizeMethodBase"]:
+    ) -> "QuantizeMethodBase | None":
         if isinstance(layer, FusedMoE):
             from vllm.model_executor.layers.quantization.moe_wna16 import MoeWNA16Config