f Build RBF test with UniFFI

Convert the explicit fee rate through Into so the anchor-reserve
RBF test builds with both the native and UniFFI fee-rate APIs.

Co-Authored-By: HAL 9000

Author: tnull

tests/integration_tests_rust.rs

@@ -3076,7 +3076,7 @@ async fn onchain_fee_bump_rbf_respects_anchor_reserve() {
 	let high_fee_rate = bitcoin::FeeRate::from_sat_per_kwu(20_000);
 	assert_eq!(
 		Err(NodeError::InsufficientFunds),
-		node_b.onchain_payment().bump_fee_rbf(payment_id, Some(high_fee_rate))
+		node_b.onchain_payment().bump_fee_rbf(payment_id, Some(high_fee_rate.into()))
 	);
 }