multi: update to fn v2

watchtower/wtdb/client_chan_summary.go

@@ -3,7 +3,7 @@ package wtdb
 import (
 	"io"
 
-	"github.com/lightningnetwork/lnd/fn"
+	"github.com/lightningnetwork/lnd/fn/v2"
 	"github.com/lightningnetwork/lnd/lnwire"
 )
 

watchtower/wtdb/client_db.go

@@ -9,7 +9,7 @@ import (
 	"sync"
 
 	"github.com/btcsuite/btcd/btcec/v2"
-	"github.com/lightningnetwork/lnd/fn"
+	"github.com/lightningnetwork/lnd/fn/v2"
 	"github.com/lightningnetwork/lnd/kvdb"
 	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/lightningnetwork/lnd/tlv"