Set run id in update handle (#705)

* Add assertion to existing test

* Set run ID in update handle

Author: dandavison

temporalio/client.py

@@ -5412,7 +5412,7 @@ async def start_workflow_update(
             client=self._client,
             id=req.request.meta.update_id,
             workflow_id=input.id,
-            workflow_run_id=input.run_id,
+            workflow_run_id=resp.update_ref.workflow_execution.run_id,
             result_type=input.ret_type,
         )
         if resp.HasField("outcome"):

tests/worker/test_workflow.py

@@ -4590,6 +4590,8 @@ async def test_workflow_update_separate_handle(
             wait_for_stage=WorkflowUpdateStage.ACCEPTED,
         )
 
+        assert update_handle_1.workflow_run_id == handle.first_execution_run_id
+
         # Create another handle and have them both wait for update complete
         update_handle_2 = client.get_workflow_handle(
             handle.id, run_id=handle.result_run_id