polish code

Author: hect0x7

src/jmcomic/jm_config.py

@@ -411,7 +411,7 @@ def new_postman(cls, session=False, **kwargs):
 
     DEFAULT_OPTION_DICT: dict = {
         'log': None,
-        'dir_rule': {'rule': 'Bd_Pname', 'base_dir': None, 'normalize_zh': 'zh-cn'},
+        'dir_rule': {'rule': 'Bd_Pname', 'base_dir': None, 'normalize_zh': ''},
         'download': {
             'cache': True,
             'image': {'decode': True, 'suffix': None},

src/jmcomic/jm_toolkit.py

@@ -344,7 +344,7 @@ def to_zh(cls, s, target=None):
         if s is None:
             return s
 
-        if target is None:
+        if not target:
             return s
 
         try: