Add email optin attribute and protocol mappers to ol apps keycloak config

[rhysyngsun]

What are the relevant tickets?

Closes https://github.com/mitodl/hq/issues/5559#issuecomment-2392330230

Description (What does it do?)

This adds the email opt in field to the user profile attributes and also adds protocol mappers for this and the last name field so that those can come back on the openid-connect/userinfo API response.

How can this be tested?

I'm not aware of how to test this locally, I think we need to test it in a deployed test environment first.