[Openid-specs-ab] Issue #1684: [Federation] federation_entity -> federation_authority (openid/connect)

[Takahiko Kawasaki]

New issue 1684: [Federation] federation_entity -> federation_authority
https://bitbucket.org/openid/connect/issues/1684/federation-federation_entity

Takahiko Kawasaki:

In the OIDC Federation specification, `federation_entity` is defined as one of metadata type identifiers, and the specification states _“All entities participating in a federation are of this type.”_

However, considering the fact that the section for the metadata type lists `federation_fetch_endpoint`, `federation_list_endpoint` and other endpoints as properties of the metadata type, I think that `federation_authority` is a better name for the metadata type.

My proposal here is to change the identifier from `federation_entitiy` to `federation_authority` and remove the sentence _“All entities participating in a federation are of this type.”_ from the section.