Standard - 5.2. UserInfo Response should have verification rules

[Nat Sakimura]

{{{ Upon receipt of the UserInfo Response, the Client MUST verify the response in accordance with 5.5. UserInfo Response Verification of <xref target="OpenID.Messages">OpenID Connect Messages 1.0</xref>.

}}}

[Nat Sakimura]

Fix #469 - Standard. Added UserInfo Resp. Verification.

→ f2dddb9d23fe