Background permission fetching causes repos from 2nd code host to be inaccessible

Created by: dadlerj

Reported by https://app.hubspot.com/contacts/2762526/company/557475933

Described in https://sourcegraph.slack.com/archives/CHPC7UX16/p1591375494489800

The customer has a workaround in the form of disabling background permission syncing.