support vllm 0.6.0

Former-commit-id: b6681d7198

src/llamafactory/hparams/parser.py

@@ -123,7 +123,7 @@ def _check_extra_dependencies(
         require_version("mixture-of-depth>=1.1.6", "To fix: pip install mixture-of-depth>=1.1.6")
 
     if model_args.infer_backend == "vllm":
-        require_version("vllm>=0.4.3", "To fix: pip install vllm>=0.4.3")
+        require_version("vllm>=0.4.3,<=0.6.0", "To fix: pip install vllm>=0.4.3,<=0.6.0")
 
     if finetuning_args.use_galore:
         require_version("galore_torch", "To fix: pip install galore_torch")