Explicitly setting encoding in tokenization_utils_base.py (huggingface#38553)

Update tokenization_utils_base.py

Add encoding explicitly

Author: Muqi1029

src/transformers/tokenization_utils_base.py

@@ -2086,7 +2086,7 @@ def _from_pretrained(
         chat_template_file = resolved_vocab_files.pop("chat_template_file", None)
         extra_chat_templates = [key for key in resolved_vocab_files if key.startswith("chat_template_")]
         if chat_template_file is not None:
-            with open(chat_template_file) as chat_template_handle:
+            with open(chat_template_file, encoding="utf-8") as chat_template_handle:
                 chat_templates["default"] = chat_template_handle.read()
         for extra_chat_template in extra_chat_templates:
             template_file = resolved_vocab_files.pop(extra_chat_template, None)