Relaxed clippy fixes/nits (#2661)

This PR contains just a few clippy fixes and nits, which are, however,
relaxed by workspace clippy settings here:
https://github.com/paritytech/polkadot-sdk/blob/master/Cargo.toml#L483-L506

---------

Co-authored-by: Dmitry Sinyavin <dmitry.sinyavin@parity.io>
Co-authored-by: ordian <write@reusable.software>
Co-authored-by: command-bot <>
Co-authored-by: Bastian Köcher <git@kchr.de>

polkadot/runtime/common/src/claims.rs

@@ -561,7 +561,7 @@ impl<T: Config> Pallet<T> {
 		}
 
 		// We first need to deposit the balance to ensure that the account exists.
-		CurrencyOf::<T>::deposit_creating(&dest, balance_due);
+		let _ = CurrencyOf::<T>::deposit_creating(&dest, balance_due);
 
 		// Check if this claim should have a vesting schedule.
 		if let Some(vs) = vesting {