Changes to Per-site metadata (colors, icons, plan support).

added ApiErrorObject to the response body oneOf list for the response status 400

removed GatewayError from the response body oneOf list for the response status 400

added ApiErrorResponse GatewayError to the response body oneOf list for the response status 400

the response's body type changed from array to object for status 200

the response's body type changed from object to no type for status 400

removed the optional property code from the response with the 400 status

removed the optional property code from the response with the 401 status

removed the optional property code from the response with the 500 status

removed the optional property field from the response with the 400 status

removed the optional property field from the response with the 401 status

removed the optional property field from the response with the 500 status

removed the optional property message from the response with the 400 status

removed the optional property message from the response with the 401 status

removed the optional property message from the response with the 500 status

added the non-success response with the status 403

added the non-success response with the status 429

added the optional property data to the response with the 401 status

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

added the required property data to the response with the 200 status

added the required property error to the response with the 500 status

added the required property errors to the response with the 401 status