Fix some datanode instance not stopped in unit tests (#21385)

Signed-off-by: Congqi Xia <congqi.xia@zilliz.com>

internal/datanode/data_node_test.go

@@ -185,6 +185,7 @@ func TestDataNode(t *testing.T) {
 	t.Run("Test BackGroundGC", func(t *testing.T) {
 		ctx, cancel := context.WithCancel(context.Background())
 		node := newIDLEDataNodeMock(ctx, schemapb.DataType_Int64)
+		defer node.Stop()
 
 		vchanNameCh := make(chan string)
 		node.clearSignal = vchanNameCh

internal/datanode/flow_graph_manager_test.go

@@ -45,6 +45,7 @@ func TestFlowGraphManager(t *testing.T) {
 	defer etcdCli.Close()
 
 	node := newIDLEDataNodeMock(ctx, schemapb.DataType_Int64)
+	defer node.Stop()
 	node.SetEtcdClient(etcdCli)
 	err = node.Init()
 	require.Nil(t, err)