Fix encoding error in utils.py (#882)

* Fix encoding error in utils.py

Non-ASCII colon sign being used and causing error on local deployment during every localhost startup.

* Update utils.py

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Co-authored-by: Chuan Hu <[email protected]>

modules/utils.py

@@ -668,7 +668,7 @@ def new_auto_history_filename(username):
         with open(os.path.join(HISTORY_DIR, username, latest_file + ".json"), 'r', encoding="utf-8") as f:
             if len(f.read()) == 0:
                 return latest_file
-    now = i18n("新对话 ") + datetime.datetime.now().strftime('%m-%d %H꞉%M')
+    now = i18n("新对话 ") + datetime.datetime.now().strftime('%m-%d %H-%M')
     return f'{now}.json'
 
 def get_history_filepath(username):