missing backtick (#1708)

NEWS.md

@@ -3,7 +3,7 @@ rmarkdown 1.19
 
 - The `encoding` argument is no longer passed to the `intermediates_generator` of R Markdown output formats. The `intermediates_generator` function can only accept arguments `input_file` and `intermediates_dir` now (see `?rmarkdown::output_format`). This is a breaking change to developers. If you are an output format developer, you have to remove the `encoding` argument in your `intermediates_generator` if your output format uses this function.
 
-- The `encoding` argument is no longer passed to the `render` element of the site generator (see `?rmarkdown::render_site).
+- The `encoding` argument is no longer passed to the `render` element of the site generator (see `?rmarkdown::render_site`).
 
 - The `encoding` argument has been removed from many of the internal functions in the **rmarkdown** package. Now all input files are assumed to be encoded in UTF-8. If you see an error message like "Error in `FUN(arg = ...)`: unused argument (`arg = ...`)", please file an issue (with a reproducible example) to https://github.com/rstudio/rmarkdown.