make fields optional in Pydantic v2

Author: giancarloromeo

packages/models-library/src/models_library/api_schemas_webserver/wallets.py

@@ -13,9 +13,9 @@
 class WalletGet(OutputSchema):
     wallet_id: WalletID
     name: IDStr
-    description: str | None
+    description: str | None = None
     owner: GroupID
-    thumbnail: str | None
+    thumbnail: str | None = None
     status: WalletStatus
     created: datetime
     modified: datetime