### 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
}
    content_type = headers.get("Content-Type", "").lower()
    content_type_is_text = any(text_type in content_type for text_type in ["text", "json", "xml"])
    is_base64_encoded = not (data.isascii() and content_type_is_text) if data else False
    body = base64.b64encode(data).decode() if is_base64_encoded else data
    ignored_headers = ["connection", "x-localstack-tgt-api", "x-localstack-request-url"]
    event_headers = {k.lower(): v for k, v in headers.items() if k.lower() not in ignored_headers}
    event_headers.update(
        {
            "x-amzn-tls-cipher-suite": "ECDHE-RSA-AES128-GCM-SHA256",
            "x-amzn-tls-version": "TLSv1.2",
            "x-forwarded-proto": "http",
            "x-forwarded-for": source_ip,
            "x-forwarded-port": str(config.EDGE_PORT),
        }
    )
    event = {
        "version": "2.0",
        "routeKey": "$default",
        "rawPath": raw_path,
        "rawQueryString": raw_query_string,
        "headers": event_headers,
        "queryStringParameters": query_string_parameters,
        "requestContext": request_context,
        "body": body,
        "isBase64Encoded": is_base64_encoded,
    }
    if not data:
        event.pop("body")
    return event