After reporting an error to the vault backend, workers call logging.exception: https://forge.softwareheritage.org/source/swh-vault/browse/master/swh/vault/cookers/base.py$154
and this should be captured by Sentry, but it isn't.
I don't understand why, as vault workers use the same plumbling as loader workers (ie. https://forge.softwareheritage.org/source/swh-scheduler/browse/master/swh/scheduler/celery_backend/config.py$157-167)