https://eaflood.atlassian.net/browse/WC-489

Users sometimes go through the assisted digital route to renew because they cannot access their account. When a user goes through WorldPay for payment, we send the account email through to WorldPay, which it then uses to send confirmation of the payment. If the user is AD because they can't access the account, this makes the confirmation meaningless.

So if a renewal is done via assisted digital, we should be passing the contact email to WorldPay, and not the account email.

The XML should use a different email address when the renewal is AD, so we need a new fixture and a new spec.

Improve the specs to handle this.

We do this by checking if the current user's email matches the renewal account email. If they do, then the user who owns the registration is doing the renewal and it must be digital. If they don't, then another user is doing the renewal on their behalf and it must be assisted digital.