itest: fix assertion for grouped asset chan itest

We should only have 2 outputs, the test asserted 3 before as the co-op
close transaction couldn't properly spend the funding input. We
also assert the normal balance now as now that we import the funding
outputs as proofs, this no longer incorrectly shows up as the balance.

Author: Roasbeef

itest/assets_test.go

@@ -895,6 +895,8 @@ func waitForSendEvent(t *testing.T,
 	sendEvents taprpc.TaprootAssets_SubscribeSendEventsClient,
 	expectedState tapfreighter.SendState) {
 
+	t.Helper()
+
 	for {
 		sendEvent, err := sendEvents.Recv()
 		require.NoError(t, err)
@@ -911,6 +913,8 @@ func closeAssetChannelAndAssert(t *harnessTest, net *NetworkHarness,
 	assetID, groupKey []byte, universeTap *tapClient, remoteBtcBalance,
 	remoteAssetBalance bool) {
 
+	t.t.Helper()
+
 	ctxb := context.Background()
 	ctxt, cancel := context.WithTimeout(ctxb, defaultTimeout)
 	defer cancel()

itest/litd_custom_channels_test.go

@@ -882,14 +882,9 @@ func testCustomChannelsGroupedAsset(_ context.Context, net *NetworkHarness,
 		false,
 	)
 
-	// For some reason, the channel funding output of the immediately closed
-	// channel is still present in the asset DB, even after we import the
-	// co-op close transaction proof.
-	// TODO(guggero): Investigate this. The actual number of outputs should
-	// be two here, and we shouldn't have the extra fundingAmount in the
-	// balance.
-	charlieAssetBalance += fundingAmount
-	assertNumAssetOutputs(t.t, charlieTap, assetID, 3)
+	// Charlie should have asset outputs: the left over change from the
+	// channel funding, and the new close output.
+	assertNumAssetOutputs(t.t, charlieTap, assetID, 2)
 
 	// The asset balances should still remain unchanged.
 	assertAssetBalance(t.t, charlieTap, assetID, charlieAssetBalance)