docs: safeguard example

Author: maelle

R/mock2-helpers.R

@@ -12,8 +12,9 @@
 #'
 #' @examples
 #' # inside local_mocked_bindings()
-#' readline <- NULL
+#' \dontrun{
 #' local_mocked_bindings(readline = mock_output_sequence(c("3", "This is a note", "n")))
+#' }
 #' # for understanding
 #' mocked_sequence <- mock_output_sequence(c("3", "This is a note", "n"))
 #' mocked_sequence()