CRAN Submission for 0.71.1 (#3311)

* fix for CRAN manual checks

* fix for CRAN manual checks

* pass local check

* fix variable naming style

* Adding Philip's record

R-package/R/callbacks.R

@@ -691,11 +691,6 @@ cb.gblinear.history <- function(sparse=FALSE) {
 #' For an \code{xgb.cv} result, a list of such matrices is returned with the elements
 #' corresponding to CV folds.
 #'
-#' @examples
-#' \dontrun{
-#' See \code{\link{cv.gblinear.history}}
-#' }
-#'
 #' @export
 xgb.gblinear.history <- function(model, class_index = NULL) {