fix: Fix wrong time stamp creation for benchmark executions via explicilty assigning UTC timezone

Author: Merlin Kallenborn

src/intelligence_layer/evaluation/benchmark/studio_benchmark.py

@@ -1,6 +1,6 @@
 import itertools
 from collections.abc import Sequence
-from datetime import datetime
+from datetime import datetime, timezone
 from http import HTTPStatus
 from typing import Any, Optional
 
@@ -99,7 +99,7 @@ def execute(
         labels: Optional[set[str]] = None,
         metadata: Optional[dict[str, Any]] = None,
     ) -> str:
-        start = datetime.now()
+        start = datetime.now(timezone.utc)
 
         runner = Runner(
             task,
@@ -122,7 +122,7 @@ def execute(
             metadata=metadata,
         )
 
-        end = datetime.now()
+        end = datetime.now(timezone.utc)
 
         evaluation_lineages = list(
             self.evaluator.evaluation_lineages(evaluation_overview.id)