### 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
timestamp = timestamp or datetime.utcnow()
    return isoformat_milliseconds(timestamp) + "+0000"
def format_timestamp_for_event_source_mapping():
    
    return datetime.utcnow().timestamp()
def add_event_source(data):
    region = LambdaRegion.get()
    mapping = build_mapping_obj(data)
    region.event_source_mappings.append(mapping)
    EventSourceListener.start_listeners(mapping)
    return mapping
def update_event_source(uuid_value, data):