Fail PendingInboundPayments after their expiry time is reached

Author: TheBlueMatt

lightning/src/ln/channelmanager.rs

@@ -3712,6 +3712,10 @@ where
 					});
 					!htlcs.is_empty() // Only retain this entry if htlcs has at least one entry.
 				});
+				let mut payment_secrets = self.pending_inbound_payments.lock().unwrap();
+				payment_secrets.retain(|_, inbound_payment| {
+					inbound_payment.expiry_height > height
+				});
 			}
 		}