Fixed UTC-related issue in tests

Author: tisnik

src/app/endpoints/query.py

@@ -237,9 +237,7 @@ async def query_endpoint_handler(
         quota_limiters=configuration.quota_limiters, user_id=user_id
     )
 
-    completed_at = datetime.datetime.now(datetime.UTC).strftime(
-        "%Y-%m-%dT%H:%M:%SZ"
-    )
+    completed_at = datetime.datetime.now(datetime.UTC).strftime("%Y-%m-%dT%H:%M:%SZ")
     conversation_id = normalize_conversation_id(responses_params.conversation)
 
     logger.info("Storing query results")

tests/unit/app/endpoints/test_conversations_v2.py

@@ -2,7 +2,7 @@
 
 """Unit tests for the /conversations REST API endpoints."""
 
-from datetime import datetime, timezone
+from datetime import datetime, UTC
 from typing import Any, cast
 
 import pytest
@@ -361,9 +361,7 @@ async def test_successful_retrieval(
         mocker.patch("app.endpoints.conversations_v2.configuration", mock_configuration)
 
         timestamp_str = "2024-01-01T00:00:00Z"
-        timestamp_dt = datetime.fromisoformat(timestamp_str).replace(
-            tzinfo=timezone.utc
-        )
+        timestamp_dt = datetime.fromisoformat(timestamp_str).replace(tzinfo=UTC)
         timestamp = timestamp_dt.timestamp()
 
         mock_configuration.conversation_cache.list.return_value = [