docs: fix URL to Plotly reference (#2457)

Author: salim-b

R/layout.R

@@ -2,7 +2,7 @@
 #' 
 #' @param p A plotly object.
 #' @param ... Arguments to the layout object. For documentation,
-#' see \url{https://plotly.com/r/reference/#Layout_and_layout_style_objects}
+#' see \url{https://plotly.com/r/reference/layout/}
 #' @param data A data frame to associate with this layout (optional). If not 
 #' provided, arguments are evaluated using the data frame in [plot_ly()].
 #' @author Carson Sievert