I have an object payload, where one of the key-value pair is an array inside the object. How can I convert that key-value pair to string.

Input:

```
{
   "key1":{
      "sk1":"abc",
      "sk2":12,
      "key2":[
         "aa",
         "bbb",
         "ccc",
         "ddd"
      ]
   }
}

```

Expected Output:

```
{
   "key1": "sk1: abc, sk2:12, key2: aa,bbb,ccc,ddd"
}

```

Thanks in advance