surveillance_true_confirmation_rate

[Hanmeng-Xu]

#' @name surveillance_true_confirmation_rate
#' @title surveillance_true_confirmation_rate
#' @description surveillance_true_confirmation_rate
#' @param country country code
#' @param admin_level admin level
#' @return
#' @export
#' @include

1. return error message if the raster file does not exist in the intermediate_raster folder.