Incomplete mdoc non-normative example

[cre8]

According to the spec:
proof_types_supported: OPTIONAL. Object that describes specifics of the key proof(s) that the Credential Issuer supports. It MUST be present if cryptographic_binding_methods_supported is present, and omitted otherwise.

But the example in section A2.2 include the cryptographic_binding_methods_supported, but not the proof_types_supported. All other examples for e.g. sd-jwt-vc do.

Either cryptographic_binding_methods_supported gets removed or proof_types_supported will be added. I would suggest to add it to be aligned with the other examples.