attestation and attestationObject is missing some of interfaces for assertions

[Kieun]

Proposed Change

WebAuthn Level 3 supports attestation in assertions, if the relying party requests an attestation and the authenticator supports attestation in assertions.

In some interfaces, such spec changes are not well reflected to the specification.
Followings are the contents which needs to be modified.

1. In Section 5.1.9, parseRequestOptionsFromJSON() method has a parameter indicating assertion options represented by JSON structure (PublicKeyCredentialRequestOptionsJSON). The PublicKeyCredentialRequestOptionsJSON structure does not have a attestation field, while the corresponding dictionary, PublicKeyCredentialRequestOptions does have a attestation field.
2. Similar to the previous issue, in AuthenticatorAssertionResponse section, the AuthenticatorAssertionResponseJSON does not have attestationObject field in it, which is not well reflected by the corresponding dictionary AuthenticatorAssertionResponse.
3. Such modification also needs to be reflected to the IDL Index.