Support users to notify for work request in SSO custom attributes

Many large organizations are interested in adopting work requests to better track their matrixed dependency workflows but are running into limitations that prevent them from being able to do it at scale.

Today when selecting which users to notify for work requests, this is a manual step for each workspace. It would be really helpful to have this added as a custom attribute in SSO settings so large organizations could do this in bulk and effectively maintain which users should be notified across the organization.

This would align to the role permissions and product prefix that are already able to be set through SSO custom attributes.