### 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
cleanup_fns = []
    yield cleanup_fns
    for cleanup_callback in cleanup_fns[::-1]:
        try:
            cleanup_callback()
        except Exception as e:
            LOG.warning("Failed to execute cleanup", exc_info=e)
@pytest.hookimpl
def pytest_configure(config: Config):
    
    config.addinivalue_line(
        "markers",
        "only_localstack: mark the test as incompatible with AWS / can't be run with AWS_CLOUD target",
    )
@pytest.hookimpl
def pytest_collection_modifyitems(config: Config, items: list[Item]):
    only_localstack = pytest.mark.skipif(
        os.environ.get("TEST_TARGET") == "AWS_CLOUD",
        reason="test only applicable if run against localstack",
    )
    for item in items:
        if "only_localstack" in item.keywords:
            item.add_marker(only_localstack)