Changes to Update an external gateway

added the new optional request property data/attributes/idempotency_window_mins

added the optional property data/attributes/idempotency_window_mins to the response with the 200 status

request property data/type was restricted to a list of enum values

added the new optional request property data/attributes/_disable

added the new optional request property data/attributes/_enable

added the new optional request property data/attributes/_regenerate_shared_secret

added the new optional request property data/attributes/_reset_circuit

added the new optional request property data/attributes/external_includes

added the new optional request property data/attributes/force_payments

the request property data/attributes/authorize_url became nullable

the request property data/attributes/capture_url became nullable

the request property data/attributes/metadata became nullable

the request property data/attributes/reference became nullable

the request property data/attributes/reference_origin became nullable

the request property data/attributes/refund_url became nullable

the request property data/attributes/token_url became nullable

the request property data/attributes/void_url became nullable

the type request property default value external_gateways was removed

added the new external_gateways enum value to the request property data/type

added the media type application/vnd.api+json for the response with the status 200