### Is there an existing issue for this?

- [X] I have searched the existing issues

### Feature description

Basically we want to only run the lambda when an insert is occurring in DynamoDB.
I tested using Dynobase deleting a record and the lambda still triggered.

```
resource "aws_lambda_event_source_mapping" "event-log" {
	event_source_arn  = aws_dynamodb_table.event-log.stream_arn
	function_name     = module.main.lambda-arn
	starting_position = "LATEST"
	enabled = true # change to false when truncating the table in localstack
	maximum_retry_attempts = 1 # limit retry on failure to 1 for now

	# https://dev.to/aws-builders/filtering-dynamodb-streams-before-lambda-p5p
	filter_criteria { # Doesn't seem to work on LocalStack for now
		filter {
			pattern = jsonencode({
				body = {
					eventName : ["INSERT"]
				}
			})
		}
	}
}
```


### 🧑‍💻 Implementation

_No response_

### Anything else?

 https://dev.to/aws-builders/filtering-dynamodb-streams-before-lambda-p5p
"""
        to be implemented by subclasses
        :returns: An AWS service client instance for communicating with the appropriate API
        """
        raise NotImplementedError
    def _get_stream_description(self, stream_client, stream_arn):
        """
        to be implemented by subclasses
        :returns: The stream description object returned by the client's describe_stream method
        """
        raise NotImplementedError
    def _get_shard_iterator(self, stream_client, stream_arn, shard_id, iterator_type):
        """
        to be implemented by subclasses
        :returns: The shard iterator object returned by the client's get_shard_iterator method
        """
        raise NotImplementedError
    def _create_lambda_event_payload(
        self, stream_arn: str, records: List[Dict], shard_id: Optional[str] = None
    ) -> Dict:
        """
        to be implemented by subclasses
        Get an event payload for invoking a Lambda function using the given records and stream metadata
        :param stream_arn: ARN of the event source stream
        :param records: Batch of records to include in the payload, obtained from the source stream
        :param shard_id: ID of the shard the records came from. This is only needed for Kinesis event payloads.
        :returns: An event payload suitable for invoking a Lambda function
        """
        raise NotImplementedError
    def _get_starting_and_ending_sequence_numbers(