OpenID Connect can return an id_token as part of the refresh_token grant type

[c0ntax]

The refreshToken() method in OpenIDConnectClient doesn't seem to allow for the setting of the id_token if it is present in the response payload. The OpenID Connect spec suggests that the id token is something that may come back with the response: https://openid.net/specs/openid-connect-core-1_0.html#RefreshTokenResponse

Given that it is possible, maybe the code should also add it to the OpenIDConnectClient data so that it can be accessed via the getIdTokenPayload method?