message: Fix compile error on 1.20
diff: @@ -72,7 +72,7 @@ pub fn line_comparison(
  let max = all_curves
  .iter()
  - .map(|(_id, data)| Sample::new(data).mean())
  + .map(|&(_id, data)| Sample::new(data).mean())
  .fold(::std::f64::NAN, f64::max);
  let (scale, prefix) = scale_time(max);
  