### Description

Airflow provides the Amazon DynamoDB to Amazon S3 below.  
https://airflow.apache.org/docs/apache-airflow-providers-amazon/stable/operators/transfer/dynamodb_to_s3.html

Most of Data Engineer build their "export DDB data to s3" pipeline using "within the point in time recovery window".   
https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/dynamodb.html#DynamoDB.Client.export_table_to_point_in_time

I appreciate if airflow has this function as a native function.  

### Use case/motivation

My daily batch job exports its data with pitr option. All of tasks is written by apache-airflow-providers-amazon except "export_table_to_point_in_time" task. 
"export_table_to_point_in_time" task only used the python operator. I expect I can unify the task as apache-airflow-providers-amazon library. 

### Related issues

_No response_

### Are you willing to submit a PR?

- [X] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

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from __future__ import annotations
import json
from datetime import datetime
from decimal import Decimal
from unittest.mock import MagicMock, patch
import pytest
from airflow import DAG
from airflow.exceptions import AirflowProviderDeprecationWarning
from airflow.models import DagRun, TaskInstance
from airflow.providers.amazon.aws.transfers.base import _DEPRECATION_MSG
from airflow.providers.amazon.aws.transfers.dynamodb_to_s3 import (
    DynamoDBToS3Operator,
    JSONEncoder,
)
from airflow.utils import timezone
class TestJSONEncoder: