基于VUE+elementUI表格的行合并

后端返回列表数据格式：

{
    "respCode":"0",
    "respMsg":"success!",
    "result":[
        {
            "riskIndexList":[
                {
                    "riskItemsName":"xxxxxxxxxxxxxx",
                    "riskItemsScore":10
                }
            ],
            "riskIndexName":"指标1"
        },
        {
            "riskIndexList":[
                {
                    "riskItemsName":"xxxxxxxxxxxxxx",
                    "riskItemsScore":78
                },
                {
                    "riskItemsName":"xxxxxxxxxxxxxx",
                    "riskItemsScore":24
                }
            ],
            "riskIndexName":"指标2"
        },
        {
            "riskIndexList":[
                {
                    "riskItemsName":"xxxxxxxxxxxxxx",
                    "riskItemsScore":61
                },
                {
                    "riskItemsName":"xxxxxxxxxxxxxx",
                    "riskItemsScore":88
                },
                {
                    "riskItemsName":"xxxxxxxxxxxxxx",
                    "riskItemsScore":5
                }
            ],
            "riskIndexName":"指标3"
        }
    ]
}

前端处理：