### Description

I want to add support of a separate AWS connection for DynamoDB in `DynamoDBToS3Operator` in `apache-airflow-providers-amazon` via `aws_dynamodb_conn_id` constructor argument.



### Use case/motivation

Sometimes DynamoDB tables and S3 buckets live in different AWS accounts so to access both resources you need to assume a role in another account from one of them.
That role can be specified in AWS connection, thus we need to support two of them in this operator.

### 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)

"""  
    template_fields: Sequence[str] = (
        "s3_bucket_name",
        "s3_key_prefix",
        "dynamodb_table_name",
    )
    template_fields_renderers = {
        "dynamodb_scan_kwargs": "json",
    }
    def __init__(
        self,
        *,
        dynamodb_table_name: str,
        s3_bucket_name: str,
        file_size: int,
        dynamodb_scan_kwargs: dict[str, Any] | None = None,
        s3_key_prefix: str = "",
        process_func: Callable[[dict[str, Any]], bytes] = _convert_item_to_json_bytes,
        aws_conn_id: str = "aws_default",
        **kwargs,
    ) -> None:
        super().__init__(**kwargs)
        self.file_size = file_size
        self.process_func = process_func
        self.dynamodb_table_name = dynamodb_table_name
        self.dynamodb_scan_kwargs = dynamodb_scan_kwargs
        self.s3_bucket_name = s3_bucket_name
        self.s3_key_prefix = s3_key_prefix
        self.aws_conn_id = aws_conn_id
    def execute(self, context: Context) -> None: