Accepting an invitation with an invalid DID should fail

[gmulhearn-anonyome]

accept_invitation for invitee current will succeed even if the DID within the Public DID invitation is invalid. This is because the implementation for into_did_doc will assume a default service of AriesService::default(), which is full of dummy data, and then that default is used in the case that resolving the DID from the ledger fails...

Default logic found here; https://github.com/hyperledger/aries-vcx/blob/main/aries_vcx/src/common/ledger/transactions.rs#L102

E.g.

let invitation = PublicInvitation::with_decorators(
            random_id(),
            PublicInvitationContent::new("label".to_string(), "InvalidDID!!!".to_string()),
            NoDecorators,
        );

will result in InviteeConnection<Invited> after accept_invitation, and the did_doc will be:

{
id: InvalidDID!!!,
public_key: [],
authentication: [],
service: {
   id: did:example:123456789asdfasdf,
   service_endpoint: https://dummy.dummy/dummy,
   recipient_keys: [],
   routing_keys: []
}
} 

IMO it should just fail to accept if the diddoc cannot be properly resolved