multi: rename FetchLightningNode

to FetchNode

discovery/gossiper.go

@@ -2235,7 +2235,7 @@ func (d *AuthenticatedGossiper) processZombieUpdate(_ context.Context,
 func (d *AuthenticatedGossiper) fetchNodeAnn(ctx context.Context,
 	pubKey [33]byte) (*lnwire.NodeAnnouncement, error) {
 
-	node, err := d.cfg.Graph.FetchLightningNode(ctx, pubKey)
+	node, err := d.cfg.Graph.FetchNode(ctx, pubKey)
 	if err != nil {
 		return nil, err
 	}

discovery/gossiper_test.go

@@ -295,7 +295,7 @@ func (r *mockGraphSource) GetChannelByID(chanID lnwire.ShortChannelID) (
 	return &chanInfo, edge1, edge2, nil
 }
 
-func (r *mockGraphSource) FetchLightningNode(_ context.Context,
+func (r *mockGraphSource) FetchNode(_ context.Context,
 	nodePub route.Vertex) (*models.Node, error) {
 
 	for _, node := range r.nodes {