Return dispatch_fee_payment from message details RPC (#1014)

bridges/modules/messages/src/benchmarking.rs

@@ -76,7 +76,7 @@ pub struct MessageProofParams {
 	pub outbound_lane_data: Option<OutboundLaneData>,
 	/// Proof size requirements.
 	pub size: ProofSize,
-	/// If true, dispatch fee is paid at the target chain (if supported by configuration).
+	/// Where the fee for dispatching message is paid?
 	pub dispatch_fee_payment: DispatchFeePayment,
 }