queue.shutdown allows jobs to both fail and complete simoultaneously.

I'm trying to get gracefull shutdown to work in a distributed setting and I am having the issue that when using `queue.shutdown` with a `timeout` value.
The job will both complete normally (`done` gets called) and it will fail with a `Shutdown` message.
Is this a bug or have i misinterpreted:
> Workers will wait timeout milliseconds for their active job's done to be called or mark the active job failed with shutdown error reason

From the documentation it reads as the job will either complete normally or be failed.

Start by reproducing queue.shutdown(timeout) with distributed workers and record whether done is called before the Shutdown failure. Compare the observed behavior with the quoted documentation; simultaneous completion and failure would confirm the reported bug.

Written by the indexing model from the issue text.