fix "tansformers_module" ModuleNotFoundError when load model with trust_remote_code=True (#871)

vllm/engine/ray_utils.py

@@ -11,7 +11,11 @@ try:
         """Ray wrapper for vllm.worker.Worker, allowing Worker to be
         lazliy initialized after Ray sets CUDA_VISIBLE_DEVICES."""
 
-        def __init__(self) -> None:
+        def __init__(self, init_cached_hf_modules=False) -> None:
+            if init_cached_hf_modules:
+                # pylint: disable=import-outside-toplevel
+                from transformers.dynamic_module_utils import init_hf_modules
+                init_hf_modules()
             self.worker = None
 
         def init_worker(self, worker_init_fn):