dagre布局上层某个节点连接到多个下层节点时，计算出的节点位置会有偏差

[NewAwesome]

复现方式

• 进入测试demo页面：https://observablehq.com/d/2db6b0cc5e97d8d6#cell-1668
• 修改 data6 图数据（下方复制粘贴）并保存
• 查看布局效果（节点1-3连接节点2-2、2-3会发生位置偏差，但节点1-3连接节点2-1、2-3的话就不会）

节点、边数据

data6 = {
  return {
    nodes: [
      {
        id: "1",
        data: {
          name: "alps_file1"
        }
      },
      {
        id: "1-1",
        data: {
          name: "alps_file2"
        }
      },
      {
        id: "1-2",
        data: {
          name: "alps_file3"
        }
      },
      {
        id: "1-3",
        data: {
          name: "sql_file1"
        }
      },
      {
        id: "2-1",
        data: {
          name: "sql_file2"
        }
      },
      {
        id: "2-2",
        data: {
          name: "feature_etl_1"
        }
      },
      {
        id: "2-3",
        data: {
          name: "feature_etl_1"
        }
      }
    ],
    edges: [
      {
        id: "e1",
        data: {},
        source: "1",
        target: "1-1"
      },
      {
        id: "e2",
        data: {},
        source: "1",
        target: "1-2"
      },
      {
        id: "e3",
        data: {},
        source: "1",
        target: "1-3"
      },
      {
        id: "e4",
        data: {},
        source: "1-1",
        target: "2-1"
      },
      {
        id: "e5",
        data: {},
        source: "1-2",
        target: "2-2"
      },
      {
        id: "e6",
        data: {},
        source: "1-3",
        target: "2-3"
      },
      {
        id: "7",
        data: {},
        source: "1-3",
        target: "2-2"
      }
    ]
  };
}