### 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
method, path, headers, data, query_string_params=None, is_base64_encoded=False
):
    query_string_params = query_string_params or parse_request_data(method, path, "")
    
    headers = canonicalize_headers(headers)
    return {
        "path": path,
        "headers": dict(headers),
        "multiValueHeaders": multi_value_dict_for_list(headers),
        "body": data,
        "isBase64Encoded": is_base64_encoded,
        "httpMethod": method,
        "queryStringParameters": query_string_params or None,
        "multiValueQueryStringParameters": multi_value_dict_for_list(query_string_params) or None,
    }
def process_sns_notification(
    func_arn,
    topic_arn,
    subscription_arn,
    message,
    message_id,
    message_attributes,
    unsubscribe_url,
    subject="",
):
    event = {
        "Records": [