add belle template

Former-commit-id: c489c8ecbaaa511ddc7dc1de685981531eedd38c

src/utils/config.py

@@ -141,9 +141,9 @@ class DataTrainingArguments:
         default=0,
         metadata={"help": "Proportion of the dataset to include in the development set, should be between 0.0 and 1.0."}
     )
-    prompt_template: Optional[Literal["alpaca", "vicuna", "ziya"]] = field(
+    prompt_template: Optional[str] = field(
         default="alpaca",
-        metadata={"help": "Which template to use for constructing prompts in training."}
+        metadata={"help": "Which template to use for constructing prompts in training and inference."}
     )
 
     def __post_init__(self): # support mixing multiple datasets