EPP/REPP: add auction deadlines to check request reponses

[vohmar]

Example reposnse to epp check request (partial):

    <resData>
      <domain:chkData xmlns:domain="https://epp.tld.ee/schema/domain-ee-1.2.xsd">
        <domain:cd>
          <domain:name avail="0">näiteks.ee</domain:name>
          <domain:reason>Awaiting payment</domain:reason>
        </domain:cd>
      </domain:chkData>
    </resData>

add auction deadline info to the reason value - ie if status awaiting payment then append invoice due date, i status awaiting registration then registration deadline.

example:

Awaiting payment until 2024-03-25 23:59:59 +0200