How to get the Google ID of a user from the REST API?


I need to find all users that have logged in to our Grafana using Google OAuth, and get their unique Google IDs.

From what I can see here (Grafana REST API Docs) the only relevant information returned is

"authLabels": ["OAuth"]

Is there any way to obtain the Google ID of a user? If not, are there any workarounds I could use?