f update debug_assert message and remove reachable debug_assert

Author: valentinewallace

lightning/src/onion_message/messenger.rs

@@ -1486,10 +1486,11 @@ where
 					ParsedOnionMessageContents::AsyncPayments(AsyncPaymentsMessage::ReleaseHeldHtlc(msg)) => {
 						let context = match context {
 							Some(MessageContext::AsyncPayments(context)) => context,
-							_ => {
-								debug_assert!(false, "Shouldn't have triggered this case.");
+							Some(_) => {
+								debug_assert!(false, "Checked in peel_onion_message");
 								return
 							},
+							None => return,
 						};
 						self.async_payments_handler.release_held_htlc(msg, context);
 					},