fix(oauth): Send id_token of the authorized user instead of Guest
fix(oauth): Send id_token of the authorized user instead of Guest

This only affects OAuth clients that use `id_token` obtained from `frappe.integrations.oauth2.get_token`.

Doesn't affect OAuth clients that ignore id_token and explicitly use `frappe.integrations.oauth2.openid_profile` endpoint for getting user details. e.g. Frappe OAuth client.

A simple way to replicate this is to setup Frappe-Frappe OAuth client-server pair and use `login_via_oauth2_id_token` instead of `login_via_oauth2` in `login_via_frappe`.

frappe/frappe,yashodhank/frappe,yashodhank/frappe,StrellaGroup/frappe,yashodhank/frappe,StrellaGroup/frappe,StrellaGroup/frappe,yashodhank/frappe,frappe/frappe,frappe/frappe