Call userinfo on login to enrich the login ID token

[julien-nc]

closes #1034

If, for some reason, some user information is missing from the login ID tokens but can be obtained with the userinfo endpoint, user_oidc can now optionally call the userinfo endpoint on login to enrich the data contained in the login ID token.

[jvllmr]

I mentioned this on my issue before, but this change works well for me in on test setup ✅

[juliusknorr]

Are we sure that we are properly requesting the additional information? I would expect that the extra claim for userinfo should be able to return that

user_oidc/lib/Controller/LoginController.php

Lines 188 to 193 in 92fe5e8

	// more details about requesting claims:
	// https://openid.net/specs/openid-connect-core-1_0.html#IndividualClaimsRequests
	// ['essential' => true] means it's mandatory but it won't trigger an error if it's not there
	// null means we want it
	'id_token' => [],
	'userinfo' => [],

https://openid.net/specs/openid-connect-core-1_0.html#IndividualClaimsRequests

I'm not a fan of all the extra settings, so mostly asking if we know a reason why this is not sent right away.