fix: remove unused imports to pass pre-commit ruff check

Signed-off-by: prashansapkota <prashan.sapkota3456@gmail.com>

Author: prashansapkota

src/tests/test_multi_api_key_auth.py

@@ -1,8 +1,7 @@
-from unittest.mock import MagicMock, patch
+from unittest.mock import MagicMock
 
 import pytest
 from fastapi import HTTPException
-from fastapi.testclient import TestClient
 
 from vllm_router.auth import _parse_api_keys, get_allowed_api_keys, verify_api_key
 

src/tests/test_stale_metrics.py

@@ -1,5 +1,5 @@
 import pytest
-from prometheus_client import REGISTRY, CollectorRegistry, generate_latest
+from prometheus_client import REGISTRY, generate_latest
 
 from vllm_router.routers.metrics_router import _LABEL_GAUGES, _clear_label_gauges
 from vllm_router.service_discovery import EndpointInfo