chore: align and register s3 print methods

NAMESPACE

 # Generated by roxygen2: do not edit by hand
 
+S3method(print,google_font)
+S3method(print,xaringanthemer_default)
 export(apply_alpha)
 export(choose_dark_or_light)
 export(darken_color)

R/style_font_default.R

   x
 }
 
-print.xaringanthemer_default <- function(x) {
+#' @export
+print.xaringanthemer_default <- function(x, ...) {
   print(unclass(x))
 }

R/utils.R

   unique(match.arg(language_codes, several.ok = TRUE))
 }
 
-print.google_font <- function(x) {
+#' @export
+print.google_font <- function(x, ...) {
   cat(
     "Family: ",
     x$family,