Relaxed requirement that decoded SHC must have a nbf property
Relaxed requirement that Smart Health Card tokens must have a IssuanceDate (nbf) property when decoding. If not found the library defaults the property to the unix epoch start time of 00:00:00 UTC on 1 January 1970.
GitHub Issue: SmartHealthCardJwsDecoder.DecodePayloadAsync(..., Verify: false) does not disable required SmartHealthCardModel json property checks #10