Allow Group Owners to change primary emails for Enterprise Users

Background

It is currently not possible for an Group Owner to change the primary email address of Enterprise Users managed by their organization. Sometimes an organization may need to update their users primary email address to match a new Domain/TLD or their SAML/SCIM configuration. Currently, each individual user would need to manually update their respective primary email address which can be cumbersome when many users need to be updated.

This was requested by a customer in Zendesk (Internal).

Proposal

Group Owners should be able to update the primary email address of Enterprise Users via the UI and/or the Users API.