Add type annotation to config_init (#26300)

Author: gwrome

mypy.ini

@@ -17,9 +17,6 @@ ignore_errors=True
 [mypy-pandas.core.computation.pytables]
 ignore_errors=True
 
-[mypy-pandas.core.config_init]
-ignore_errors=True
-
 [mypy-pandas.core.indexes.base]
 ignore_errors=True
 

pandas/core/config_init.py

@@ -277,8 +277,6 @@ def use_numexpr_cb(key):
     Valid values: False,True
 """
 
-style_backup = dict()
-
 
 def table_schema_cb(key):
     from pandas.io.formats.printing import _enable_data_resource_formatter