that is true, though contributions can be made (I mean, PR welcome!) it would be a great addition
there's also some basic scripts here https://github.com/mozilla-iam/federated_access_proxy/tree/m...
Also might be worth mentioning that there is some alternative tooling to deliver multi-factor / single sign on and short lived certificates to SSH like teleport: https://github.com/gravitational/teleport
Disclaimer: I work for Gravitational, the company behind teleport