Panic if no fee-payer found via Message::new() (#10050)

automerge

sdk/src/fee_calculator.rs

@@ -183,7 +183,7 @@ mod tests {
     #[test]
     fn test_fee_calculator_calculate_fee() {
         // Default: no fee.
-        let message = Message::new(&[]);
+        let message = Message::default();
         assert_eq!(FeeCalculator::default().calculate_fee(&message), 0);
 
         // No signature, no fee.