tweak some pattern matches to address a new clippy warning

polkadot/node/core/bitfield-signing/src/lib.rs

@@ -83,7 +83,7 @@ async fn get_core_availability(
 	sender: &Mutex<&mut impl SubsystemSender<overseer::BitfieldSigningOutgoingMessages>>,
 	span: &jaeger::Span,
 ) -> Result<bool, Error> {
-	if let &CoreState::Occupied(ref core) = core {
+	if let CoreState::Occupied(core) = core {
 		let _span = span.child("query-chunk-availability");
 
 		let (tx, rx) = oneshot::channel();

polkadot/node/subsystem-util/src/determine_new_blocks.rs

@@ -65,7 +65,7 @@ where
 	}
 
 	'outer: loop {
-		let &(ref last_hash, ref last_header) = ancestry
+		let (last_hash, last_header) = ancestry
 			.last()
 			.expect("ancestry has length 1 at initialization and is only added to; qed");
 

polkadot/runtime/parachains/src/configuration.rs

@@ -1291,7 +1291,7 @@ impl<T: Config> Pallet<T> {
 		// First, we need to decide what we should use as the base configuration.
 		let mut base_config = pending_configs
 			.last()
-			.map(|&(_, ref config)| config.clone())
+			.map(|(_, config)| config.clone())
 			.unwrap_or_else(Self::config);
 		let base_config_consistent = base_config.check_consistency().is_ok();
 

polkadot/runtime/parachains/src/inclusion/mod.rs

@@ -643,7 +643,7 @@ impl<T: Config> Pallet<T> {
 		};
 
 		// one more sweep for actually writing to storage.
-		let core_indices = core_indices_and_backers.iter().map(|&(ref c, _, _)| *c).collect();
+		let core_indices = core_indices_and_backers.iter().map(|(c, _, _)| *c).collect();
 		for (candidate, (core, backers, group)) in
 			candidates.into_iter().zip(core_indices_and_backers)
 		{

polkadot/runtime/parachains/src/paras/mod.rs

@@ -1260,13 +1260,13 @@ impl<T: Config> Pallet<T> {
 			UpcomingUpgrades::<T>::mutate(|upcoming_upgrades| {
 				*upcoming_upgrades = mem::take(upcoming_upgrades)
 					.into_iter()
-					.filter(|&(ref para, _)| !outgoing.contains(para))
+					.filter(|(para, _)| !outgoing.contains(para))
 					.collect();
 			});
 			UpgradeCooldowns::<T>::mutate(|upgrade_cooldowns| {
 				*upgrade_cooldowns = mem::take(upgrade_cooldowns)
 					.into_iter()
-					.filter(|&(ref para, _)| !outgoing.contains(para))
+					.filter(|(para, _)| !outgoing.contains(para))
 					.collect();
 			});
 		}

polkadot/runtime/parachains/src/scheduler.rs

@@ -235,7 +235,7 @@ impl<T: Config> Pallet<T> {
 	pub(crate) fn initializer_on_new_session(
 		notification: &SessionChangeNotification<T::BlockNumber>,
 	) {
-		let &SessionChangeNotification { ref validators, ref new_config, .. } = notification;
+		let SessionChangeNotification { validators, new_config, .. } = notification;
 		let config = new_config;
 
 		let mut thread_queue = ParathreadQueue::<T>::get();