fix: use typing.optional not pydantic.typing.optional

app/lists/mirror_mapping.py

@@ -1,11 +1,10 @@
 #  pylint: disable=too-few-public-methods
 
 import builtins
-from typing import Dict, List, Union
+from typing import Dict, List, Union, Optional
 
 from flask import current_app
 from pydantic import BaseModel, Field
-from pydantic.typing import Optional
 from tldextract import extract
 
 from app.models.base import Group, Pool