message: fix clone_on_copy
  an array is already `Copy`
diff: @@ -400,7 +400,7 @@ impl<'a, W: Write> JpegEncoder<'a, W> {
  200 - scale * 2
  };
  - let mut tables = vec![STD_LUMA_QTABLE.clone(), STD_CHROMA_QTABLE.clone()];
  + let mut tables = vec![STD_LUMA_QTABLE, STD_CHROMA_QTABLE];
  tables.iter_mut().for_each(|t|
  t.iter_mut().for_each(|v| {
  *v = clamp(
  