使用map数据结构的，键值唯一性进行操作

  //根据年龄分组，获取目标数据格式
  //[{key:key,data:[{}]}]
  //{key:[]}
  const arr = [
    { name:'test1',age:10},
    { name:'test2',age:20},
    { name:'test3',age:10},
    { name:'test4',age:20},
    { name:'test5',age:10},
    { name:'test6',age:20},
  ]

  let map = new Map()
  arr.map(it=>{
    map.set(it.age,[...map.get(it.age)||'',it])
  })
  
  let objs = Object.fromEntries(map.entries())
  let toArr=[]
  for(let [key,value] of map){
    toArr.push({
        key:key,
        data:value
    })
  }
  console.log(toArr,111)
  console.log(objs,222)

效果：