Add handling in logs + artifacts download script for data collection for logs that don't exist

[tt-rkim]

We see examples where logs may not exist for certain jobs because they're stuck pending (need to handle this later or at script time, probably later because it's part of API response) or GitHub runner crapped out: https://github.com/tenstorrent/tt-metal/actions/runs/10972744243/job/30469354758