Get name and photourl from invitees if setting up non-Google user and send it to Firebase auth

When createUserOnFirebaseAuthCreate is fired (which can happen if a person logs in or a user is created manually in the Firebase auth console), ET looks for a corresponding invitee document, and then writes corresponding information to a new user. This information includes the displayName and photoUrl retrieved from the newly created Firebase auth user.

But if the Firebase auth user is not a Google user, displayName and photoUrl does not exist.

So in this case, we should store this information ahead of time in invitee (displayname and photoUrl), so that we can first update it in the Firebase auth user, and then have it flow into the new Firestore user doc.