fix test

Signed-off-by: kerthcet <kerthcet@gmail.com>

Author: kerthcet

tests/integration/server/test_graphql_query.py

@@ -3,6 +3,7 @@
 # test query from graphql endpoint
 
 import asyncio
+import os
 import uuid
 from datetime import datetime, timedelta
 
@@ -419,8 +420,9 @@ async def test_query_single_run():
 
     # Force flush spans to ClickHouse
     from opentelemetry import trace
+
     tracer_provider = trace.get_tracer_provider()
-    if hasattr(tracer_provider, 'force_flush'):
+    if hasattr(tracer_provider, "force_flush"):
         tracer_provider.force_flush()
 
     # Wait a bit for spans to be written to ClickHouse