Manage Heroku enterprise-level resources (particularly enterprise users)

[evanrappe]

No debug info to include, this is a feature request, not a bug report.

We would love to be able to manage user access at the enterprise level in addition to the current team-level access that's available to set with heroku_team_member.

Today, if we add someone as a member to a team within our enterprise, Heroku also grants them base permissions on the enterprise. The issue is that when we remove someone from their team by destroying their heroku_team_member resource, the access assigned at the enterprise level never goes away.

We would either expect the enterprise-level access to be destroyed automatically when someone is removed from their last team in the enterprise, or expose the enterprise level access in Terraform so we can create/destroy it ourselves.