Update response type in get_all_tables to allow None values in dictionary

Author: X

backend/plugin/code_generator/api/v1/code.py

@@ -19,7 +19,7 @@
 @router.get('/tables', summary='获取数据库表')
 async def get_all_tables(
     table_schema: Annotated[str, Query(description='数据库名')] = 'fba',
-) -> ResponseSchemaModel[list[dict[str, str]]]:
+) -> ResponseSchemaModel[list[dict[str, str | None]]]:
     data = await gen_service.get_tables(table_schema=table_schema)
     return response_base.success(data=data)