Merge branch 'ds/background-maintenance-with-credential'

Background tasks "git maintenance" runs may need to use credential information when going over the network, but a credential helper may work only in an interactive environment, and end up blocking a scheduled task waiting for UI. Credential helpers can now behave differently when they are not running interactively. * ds/background-maintenance-with-credential: scalar: configure maintenance during 'reconfigure' maintenance: add custom config to background jobs credential: add new interactive config option