[deps] goodbye python 3.9 (#9677)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: hiyouga <16256802+hiyouga@users.noreply.github.com>
Co-authored-by: hiyouga <hiyouga@buaa.edu.cn>

src/llamafactory/hparams/evaluation_args.py

@@ -14,7 +14,7 @@
 
 import os
 from dataclasses import dataclass, field
-from typing import Literal, Optional
+from typing import Literal
 
 from datasets import DownloadMode
 
@@ -46,7 +46,7 @@ class EvaluationArguments:
         default=5,
         metadata={"help": "Number of examplars for few-shot learning."},
     )
-    save_dir: Optional[str] = field(
+    save_dir: str | None = field(
         default=None,
         metadata={"help": "Path to save the evaluation results."},
     )