We have errors in production where the job starts correctly (i.e. the
blob exists), but `blob.open` fails with a `ActiveStorage::FileNotFound`
error.
When checking later in production, the blob has been deleted.
This points to the blob (and the file) being deleted during the virus
scan job.
In that case, ignore the error (rather than retrying the job).
ActiveStorage jobs are now moved to their own queue.
For consistency, we also move our own analysis jobs (VirusScannerJob)
on the same `:active_storage_analysis` queue.
We currently have many failed VirusScannerJob enqueued, because the
underlying blob is missing.
This PR fixes the issue by discarding the job in those cases (because if
the blob is gone, the job is never going to succeed).
The implementation is based on a similar issue encoutered by the
ActiveStorage::AnalyzeJob. See 06f8baf73c
