code: func (api *API) DeleteSpectrumApplication(zoneID string, applicationID string) error {
  	uri := fmt.Sprintf(
  		"/zones/%s/spectrum/apps/%s",
  		zoneID,
  		applicationID,
  	)
  
  	_, err := api.makeRequest("DELETE", uri, nil)
  	if err != nil {
  		return errors.Wrap(err, errMakeRequestError)
  	}
  
  	return nil
  }
docs: // DeleteSpectrumApplication removes a Spectrum application based on the ID.
  //
  // API reference: https://developers.cloudflare.com/spectrum/api-reference/#delete-a-spectrum-application