An admin can delete a user in beta-galaxy.ansible.com. Notes:

1. With GitHub SSO a user can recreate their account after this, and get access to content that matches that namespace, by design.
2. Since a user does not "have" content, content is not affected by user delete. A user is part of one or more groups, the group has access to one more namespaces, and namespaces have content

TBD on what the requirements are for account deletion/deactivation beyond what we currently have, if any. Changes may affect PAH.