Snowbridge: deposit extra fee to beneficiary on Asset Hub (#4175)

Just the upper-stream for
https://github.com/Snowfork/polkadot-sdk/pull/137 and more context
there.

---------

Co-authored-by: Clara van Staden <claravanstaden64@gmail.com>
Co-authored-by: Adrian Catangiu <adrian@parity.io>

bridges/snowbridge/primitives/router/src/inbound/mod.rs

@@ -273,8 +273,10 @@ where
 			},
 			None => {
 				instructions.extend(vec![
-					// Deposit asset to beneficiary.
-					DepositAsset { assets: Definite(asset.into()), beneficiary },
+					// Deposit both asset and fees to beneficiary so the fees will not get
+					// trapped. Another benefit is when fees left more than ED on AssetHub could be
+					// used to create the beneficiary account in case it does not exist.
+					DepositAsset { assets: Wild(AllCounted(2)), beneficiary },
 				]);
 			},
 		}