funding: fix import paths for test

fundingmanager_test.go

@@ -29,10 +29,6 @@ import (
 	"github.com/lightningnetwork/lnd/lnrpc"
 	"github.com/lightningnetwork/lnd/lnwallet"
 	"github.com/lightningnetwork/lnd/lnwire"
-
-	"github.com/btcsuite/btcd/btcec"
-	"github.com/btcsuite/btcd/wire"
-	"github.com/btcsuite/btcutil"
 )
 
 const (