fedora-infra_ansible/roles/osbs-client/files

The site-customize file here additionally disables or enables plugins on top of
the default set.

The default set ships with osbs-client and can be found here:
https://github.com/projectatomic/osbs-client/blob/master/inputs/prod_inner.json

See also: https://github.com/projectatomic/osbs-client/blob/master/docs/build_process.md