protected OAuth20AccessToken getAccessToken(final String idToken, final String clientId) throws Throwable {
        val principal = RegisteredServiceTestUtils.getPrincipal("casuser",
            CollectionUtils.wrap("email", List.of("casuser@example.org")));
        return getAccessToken(principal, idToken, clientId);
    }
This is {@link AbstractOidcTests}.

@author Misagh Moayyed
@since 5.3.0
support/cas-server-support-oidc/src/test/java/org/apereo/cas/oidc/AbstractOidcTests.java