Remove remaining reference to R6 method

Author: brookslogan

R/grouped_epi_archive.R

@@ -216,7 +216,7 @@ epix_slide.grouped_epi_archive <- function(x, f, ..., before, ref_time_values,
   if ("group_by" %in% nse_dots_names(...)) {
     cli_abort("
           The `group_by` argument to `slide` has been removed; please use
-          the `group_by` S3 generic function or `$group_by` R6 method
+          the `group_by()` S3 generic function
           before the slide instead. (If you were instead trying to pass a
           `group_by` argument to `f` or create a column named `group_by`,
           this check is a false positive, but you will still need to use a