[ci] fix: fix test_engine ci (#3771)

### What does this PR do?

- fix test_engine ci for latest transformers

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.github/workflows/model.yml

@@ -208,6 +208,7 @@ jobs:
 
       - name: Running mcore engine tests on 8 L20 GPUs
         run: |
+          ray stop --force
           pytest -s -x tests/models/test_engine.py
 
   cleanup:

tests/models/test_engine.py

@@ -24,7 +24,7 @@ import ray
 import torch
 import torch.distributed as dist
 import torch.multiprocessing as mp
-from transformers import AutoModelForCausalLM, AutoModelForTokenClassification, Qwen3Config, Qwen3MoeConfig
+from transformers import AutoConfig, AutoModelForCausalLM, AutoModelForTokenClassification, Qwen3Config, Qwen3MoeConfig
 
 from verl import DataProto
 from verl.single_controller.ray import RayClassWithInitArgs, RayResourcePool, RayWorkerGroup
@@ -289,8 +289,9 @@ def _worker(rank: int, world_size: int, rendezvous_file: str, strategy: str, mod
         world_size=world_size,
     )
 
+    ref_model_config = AutoConfig.from_pretrained(model_path)
     with torch.device("meta"):
-        ref_model = AutoModelForCausalLM.from_pretrained(model_path)
+        ref_model = AutoModelForCausalLM.from_config(ref_model_config)
 
     from verl.workers.engine import BaseEngine, EngineRegistry