ci: align backend lint checks

app/api/security.py

@@ -18,14 +18,12 @@ runs in production - not a replacement.
 from __future__ import annotations
 
 import hmac
-from typing import Awaitable, Callable
+from collections.abc import Awaitable, Callable
 
 from fastapi import FastAPI, Request, Response
 from fastapi.responses import JSONResponse
 from starlette.types import ASGIApp
 
-from app.config import settings as _module_settings
-
 EXEMPT_PATHS: tuple[str, ...] = ("/", "/docs", "/redoc", "/openapi.json")
 EXEMPT_SUFFIXES: tuple[str, ...] = ("/health",)