fix R cmd check NOTE

Author: jgabry

R/mcmc-overview.R

@@ -26,7 +26,7 @@
 #' an additional column `"Chain"` that contains the chain number (an integer)
 #' corresponding to each row in the data frame.
 #' * __draws__: Any of the `draws` formats supported by the
-#' \pkg{\link{posterior}} package.
+#' \pkg{posterior} package.
 #'
 #' __Note__: typically the user should *not* include warmup iterations
 #' in the object passed to **bayesplot** plotting functions, although for