Remove useless into_iter() on Range (#9806) (#9811)

Clippy has started complaining about this on the stable branch, and it's
probably correct to do so.

(cherry picked from commit 5a9d041)

Co-authored-by: Jake Lishman <jake.lishman@ibm.com>

src/dense_layout.rs

@@ -198,7 +198,6 @@ pub fn best_subset(
             .reduce(reduce_identity_fn, reduce_fn)
     } else {
         (0..coupling_shape[0])
-            .into_iter()
             .map(map_fn)
             .reduce(reduce_fn)
             .unwrap()