Dynamically chose fee for TxRedeem.

Alice chooses the fee for TxRedeem because she is the one that cares. Note must be taken here because if the fee is too low (e.g. < min tx fee) then she might not be able to publish TxRedeem at all.

swap/tests/harness/mod.rs

@@ -35,6 +35,11 @@ use tracing_subscriber::util::SubscriberInitExt;
 use url::Url;
 use uuid::Uuid;
 
+// Note: this needs to be adopted if bitcoin::wallet.select_feerate() or
+// bitcoin::ESTIMATED_WEIGHT_TX_REDEEM changes.
+// TODO: see if there is a better way.
+const TX_REDEEM_FEE: u64 = 12500;
+
 pub async fn setup_test<T, F, C>(_config: C, testfn: T)
 where
     T: Fn(TestContext) -> F,
@@ -678,7 +683,7 @@ impl TestContext {
 
     fn alice_redeemed_btc_balance(&self) -> bitcoin::Amount {
         self.alice_starting_balances.btc + self.btc_amount
-            - bitcoin::Amount::from_sat(bitcoind::TX_FEE)
+            - bitcoin::Amount::from_sat(TX_REDEEM_FEE)
     }
 
     fn bob_redeemed_xmr_balance(&self) -> monero::Amount {