log: lower level for enqueuing errors on repo-updater
Created by: jhchabran
Following-up to https://sourcegraph.slack.com/archives/C02EDAQAJQZ/p1662124359938039, this PR lowers the loglevel for errors coming from the repo-updater. This is a very noisy error that is spamming Sentry quite a lot.
I'm unsure if we shouldn't do so more precise matching or not, whoever takes a look please take a look at this :)
Test plan
Log level change, extremely minor change.