fix: catch on correct exception type if downloading with no outputs

[marofke]

What was the problem/requirement? (What/Why)

We were still seeing a cryptic error message when trying to download outputs for a job that has no outputs (either because the job hasn't completed or there are no expected outputs).

Turns out we were catching on all exceptions and raising an AssetSyncError, when the function we were catching on raised a JobAttachmentsError if no outputs were found.

What was the solution? (How)

Catch on the JobAttachmentsError and raise it since we expect that error and handle it up the chain.

What is the impact of this change?

It's clearer to customers that there are no outputs for their job

How was this change tested?

Before fix:

deadline job download-output
Downloading output from Job 'Test'
Failed to download output from job group:

After fix:

deadline job download-output
Downloading output from Job 'Test'
There are no output files available for download at this moment. Please verify that the Job/Step/Task you are trying to download output from has completed successfully.

Was this change documented?

N/A

Is this a breaking change?

No

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