Delete unused helper

tests/worker/test_update_with_start.py

@@ -1,11 +1,9 @@
 from __future__ import annotations
 
 import uuid
-from contextlib import contextmanager
 from datetime import timedelta
 from enum import Enum
-from typing import Any, Iterator
-from unittest.mock import patch
+from typing import Any
 
 import pytest
 
@@ -294,19 +292,6 @@ async def _do_start_update_test(
             )
             assert await update_handle.result() == "update-result-1"
 
-    @contextmanager
-    def assert_network_call(
-        self,
-        expect_network_call: bool,
-    ) -> Iterator[None]:
-        with patch.object(
-            self.client.workflow_service,
-            "poll_workflow_execution_update",
-            wraps=self.client.workflow_service.poll_workflow_execution_update,
-        ) as _wrapped_poll:
-            yield
-            assert _wrapped_poll.called == expect_network_call
-
 
 async def test_update_with_start_sets_first_execution_run_id(
     client: Client, env: WorkflowEnvironment