Changes to Get a transaction.

added the new Digital Wallet enum value to the process_method response property for the response status 200

added the new QR enum value to the interaction_point response property for the response status 200

added the optional property counterparty/identity to the response with the 200 status

added the optional property counterparty/instrument to the response with the 200 status

added the optional property external_session_id to the response with the 200 status

added subschema #3: Specify Typed Identity subschema #4: Specify Typed Instrument to the counterparty response property anyOf list for the response status 200