"Job not found" when trying to get result from job with error

```
$ cli/dp2 status 92e04aa2-c64e-42a8-b19c-079fc9a5f200

Job Id: 92e04aa2-c64e-42a8-b19c-079fc9a5f200
Status: ERROR
Priority: medium

$ cli/dp2 results --output /tmp/out 92e04aa2-c64e-42a8-b19c-079fc9a5f200
Error:
Job 92e04aa2-c64e-42a8-b19c-079fc9a5f200 not found
```

At the very least, the output should be something other than "not found". I think it would be better to print "Job {...} has no results" and probably also a return code of 0 instead of 255.

Start with the `cli/dp2 status` and `cli/dp2 results` command entry points shown in the report, then trace how an ERROR job is handled when results are requested. Confirm the behavior for the provided job ID or an equivalent failed job. Done means the results command reports that the job has no results rather than saying it was not found, with the intended exit code verified.

Written by the indexing model from the issue text.