Issue #3277256: Move to thephpleague/oauth2-server 9.0

Closes #3277256

src/OpenIdConnect/OpenIdConnectIdTokenResponse.php

@@ -32,7 +32,7 @@ class OpenIdConnectIdTokenResponse extends IdTokenResponse implements LoggerAwar
   /**
    * {@inheritdoc}
    */
-  protected function getExtraParams(AccessTokenEntityInterface $accessToken) {
+  protected function getExtraParams(AccessTokenEntityInterface $accessToken): array {
     if (FALSE === $this->isOpenIDRequest($accessToken->getScopes())) {
       return [];
     }