minimize coalesce delay for tests

node/test/builder.go

@@ -29,6 +29,7 @@ import (
 	"github.com/filecoin-project/lotus/chain/actors/policy"
 	"github.com/filecoin-project/lotus/chain/gen"
 	genesis2 "github.com/filecoin-project/lotus/chain/gen/genesis"
+	"github.com/filecoin-project/lotus/chain/messagepool"
 	"github.com/filecoin-project/lotus/chain/types"
 	"github.com/filecoin-project/lotus/chain/wallet"
 	"github.com/filecoin-project/lotus/cmd/lotus-seed/seed"
@@ -53,6 +54,7 @@ import (
 
 func init() {
 	chain.BootstrapPeerThreshold = 1
+	messagepool.HeadChangeCoalesceDelay = time.Microsecond
 }
 
 func CreateTestStorageNode(ctx context.Context, t *testing.T, waddr address.Address, act address.Address, pk crypto.PrivKey, tnd test.TestNode, mn mocknet.Mocknet, opts node.Option) test.TestStorageNode {