Update StorageAuthority interface comment (#4825)
Update StorageAuthority interface comment (#4825)

The old comment referenced the StorageUpdater interface which no longer exists.
letsencrypt/boulder,bmw/boulder,jcjones/boulder,jsha/boulder,bmw/boulder,jcjones/boulder,jsha/boulder,letsencrypt/boulder,letsencrypt/boulder,jsha/boulder,jcjones/boulder,bmw/boulder,jcjones/boulder