fix: move pytest import to top of file

tests/wf_api/test_resume_concurrency.py

@@ -4,6 +4,8 @@ import asyncio
 from pathlib import Path
 from typing import Any
 
+import pytest
+
 from wf_api.models import RawWorkflowPlan
 from wf_api.operation_context import WorkflowOperationContext
 from wf_api.run_lifecycle import create_pinned_environment, persist_stopped_run
@@ -116,8 +118,6 @@ async def test_resume_run_serializes_same_run_attempts(tmp_path: Path) -> None:
     assert first_payload["status"] == "completed"
     assert first_payload["output"] == {"answer": "first"}
 
-    import pytest
-
     with pytest.raises(ValueError, match="is not interrupted"):
         await second