get_task_state fails with unknown task state in Arvados

[golharam]

PAML/src/cwl_platform/arvados_platform.py

Line 355 in 3c3e8cc

raise ValueError(f"TODO: Unknown task state: {task.container['state']}")

reports the state is 'Complete'. The exit code is 137. We were expecting 1.

We should check for a non-zero exit code