curl --request GET \
  --url https://mail-service.iran.liara.ir/api/v1/mails/{mailServerID}/messages/{messageID}/attachments/{attachmentID} \
  --header 'Authorization: <api-key>'

{
  "status": "<string>",
  "data": {
    "attachment": {
      "name": "<string>",
      "size": 123,
      "content_type": "<string>",
      "createdAt": "<string>",
      "id": "<string>",
      "data": "<string>"
    }
  }
}