[Federation] id_token_signing_alg_values_supported in RP metadata?

Issue #1514 resolved
Takahiko Kawasaki created an issue

The RP metadata of wiki.ligo.org in “A. 3.1.2. OP Evaluates the RP metadata” of OpenID Connect Federation 1.0 contains id_token_signing_alg_values_supported, but the metadata is for OPs, not for RPs.