### 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
from datetime import datetime
from io import StringIO
from random import random
from typing import Any, Dict, List, Optional, Tuple
from urllib.parse import urlparse
from flask import Flask, Response, jsonify, request
from localstack import config
from localstack.aws.accounts import get_aws_account_id
from localstack.constants import APPLICATION_JSON, LOCALHOST_HOSTNAME
from localstack.http import Request
from localstack.http import Response as HttpResponse
from localstack.services.awslambda import lambda_executors
from localstack.services.awslambda.event_source_listeners.event_source_listener import (
    EventSourceListener,
)
from localstack.services.awslambda.invocation.lambda_util import function_name_from_arn
from localstack.services.awslambda.lambda_executors import InvocationResult, LambdaContext
from localstack.services.awslambda.lambda_utils import (
    API_PATH_ROOT,
    API_PATH_ROOT_2,
    DOTNET_LAMBDA_RUNTIMES,
    LAMBDA_DEFAULT_HANDLER,
    LAMBDA_DEFAULT_RUNTIME,
    LAMBDA_RUNTIME_NODEJS14X,
    ClientError,
    error_response,
    event_source_arn_matches,
    get_executor_mode,
    get_handler_file_from_name,
    get_lambda_extraction_dir,