Add missing future annotations

Author: mongkok

debug_toolbar/utils.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import asyncio
 import functools
 import inspect

tests/panels/sqlalchemy/crud.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from sqlalchemy import Column
 from sqlalchemy.orm import Session
 

tests/testclient.py

@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import re
 import typing as t
 from urllib import parse