Fix some clippy warnings

src/rtfmt.rs

@@ -89,7 +89,7 @@ pub fn format(fmt: &str, arg: &str, clipped_str: &str) -> String {
     }
 }
 
-fn remove_last_n_chars(s: &mut String, n: usize) -> () {
+fn remove_last_n_chars(s: &mut String, n: usize) {
     match s.char_indices().nth_back(n) {
         Some((pos, ch)) => s.truncate(pos + ch.len_utf8()),
         None => s.clear(),

src/tree.rs

@@ -536,7 +536,7 @@ impl DisplayFormat for DisplayNode<'_> {
 
                 maybe_html_escape(
                     html_escape,
-                    rtfmt::format(fmt_str, &value, &clipped_str),
+                    rtfmt::format(fmt_str, &value, clipped_str),
                 )
             })
             .into()