How can I format pivot table data as % of Row Totals in R's Openxlsx2 package?

Question

I'm placing a pivot table in a workbook via R package OpenXLSX2. The data default to a format Sum Count. Is there anyway to render the data as a % of ROW Total from R. Here is a code snippet, output and preferred output:

Code

wb <- wb %>%
  wb_add_pivot_table(df, sheet = 1,dims = "B10", rows = "data_row", cols = "rating", data = "count")

Output:

Preferred Output:

One can accomplish this manually with a right click in Excel like this:

But, I need to find a way to accomplish this programmatically. Is it possible?