Defered issuance request/response updates

[dtsiflit]

The following updates have been introduced regarding deferred issuance request payload:

• Include credential_response_encryption in request payload to specify encryption specifications. Encryption params are defined anew when deferred issuance request is placed and don't have to match the encryption params included in the initial issuance request.

When placing a deferred issuance request and the Credential Issuer still requires more time it will not respond with error issuance_pending. It responds with HTTP status code 202 and interval parameter as defined in Section 8.3 is included in response.

• Update behavior of library when parsing the response to a deferred issuance request according to the above.
• If deferred credential request's credential_response_encryption included a zip algorithm and issuer supports compression before encryption, response must be decomporessed after decryption.