Make the rake mastodon:users:clear task properly clear out unconfirmed users (#1777)
Make the rake mastodon:users:clear task properly clear out unconfirmed users (#1777)

Before it cleared out user records only (e-mail, password) without
freeing up the associated username (account record). Furthermore, since
these records have no dependent records (due to no user activity)
they can be deleted quickly with delete_all instead of destroy
kibousoft/mastodon,kibousoft/mastodon,kibousoft/mastodon,kibousoft/mastodon