new-updates-sync: set umask to be more permissive for ostree operations
    
    See https://github.com/ostreedev/ostree/pull/1984 where OSTree was
    changed to try to set group write on directories. We need to set a more
    permissive umask to take advantage of it.
    
    This is all done to support writing to the OSTree repo from OpenShift
    projects that run as a random UID, but have ftpsync (gid:263) in their
    supplemental groups. For more context see: https://pagure.io/releng/issue/8811#comment-629051