Add `createdAt` field in the edv document table

[Vishwas1]

{
  "_id": {
    "$oid": "653f45c29d8d1cb7f7fa5b0a"
  },
  "indexed": []
  "jwe": {
    "protected": "eyJlbmMiOiJYQzIwUCJ9",
    "recipients": [],
    "iv": "VRR9yAWsouUxR0-5RcTIEfkGryA1dVao",
    "ciphertext": "...",
    "tag": "T4xA5AyZOtAUezCrU2wVLQ"
  },
  "encryptedData": '...'
  "id": "hs:doc:eyzyqvy4c7pp1klptfh5wupekcrzdl0n0njpeexlqvs",
  "__v": 0
}```

Add one more field called `createAt` and store timestamp (in UTC) at which this document was created.