remove explanatory comment in trailing-comma fix

Author: todor-a

src/generation/generate.rs

@@ -7618,10 +7618,6 @@ where
           items.push_signal(Signal::SpaceIfNotTrailing);
         }
         items.push_condition(conditions::indent_if_start_of_line(generated_node));
-        // When the arrow's expression body forced the call onto multiple lines and
-        // the trailing-comma configuration is `always`, emit the trailing comma
-        // before the closing paren (issue #696). `onlyMultiLine` historically did
-        // not emit a comma here, so preserve that behavior to avoid churn.
         let trailing_break_items = {
           let mut break_items = PrintItems::new();
           if matches!(trailing_commas, TrailingCommas::Always) {