Fix warnings from clippy 1.78

benches/specializations.rs

@@ -1,4 +1,4 @@
-#![allow(unstable_name_collisions)]
+#![allow(unstable_name_collisions, clippy::incompatible_msrv)]
 
 use criterion::black_box;
 use criterion::BenchmarkId;

src/adaptors/multi_product.rs

@@ -128,7 +128,7 @@ where
                     // This cartesian product had at most one item to generate and now ends.
                     self.0 = ProductEnded;
                 } else {
-                    inner.cur = next.clone();
+                    inner.cur.clone_from(&next);
                 }
                 next
             }

tests/specializations.rs

@@ -466,7 +466,7 @@ quickcheck! {
         helper(v.iter().copied());
         helper(v.iter().copied().filter(Result::is_ok));
 
-        fn helper(it: impl Iterator<Item = Result<u8, u8>> + DoubleEndedIterator + Clone) {
+        fn helper(it: impl DoubleEndedIterator<Item = Result<u8, u8>> + Clone) {
             macro_rules! check_results_specialized {
                 ($src:expr, |$it:pat| $closure:expr) => {
                     assert_eq!(