Also use uglifyjs on CentOS Stream 8
This conditional was recently changed to match VERSION_ID "8." to only
apply to RHEL 8 releases, but it should also match CentOS Stream 8 which
has VERSION_ID "8".
https://pagure.io/freeipa/c/43f344b931db3f72f50e1620443be9f21623e29a
Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>