### 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
(i for i, item in enumerate(policy["Statement"]) if item["Sid"] == statement), None
    )
    if statement_index is None:
        return not_found_error(f"Statement {statement} is not found in resource policy.")
    iam_client.delete_policy(PolicyArn=policy["PolicyArn"])
    policy["Statement"].pop(statement_index)
    description = policy.get("Description")
    policy_name = policy.get("PolicyName")
    del policy["PolicyName"]
    del policy["PolicyArn"]
    if len(policy["Statement"]) > 0 and description:
        iam_client.create_policy(
            PolicyName=policy_name,
            PolicyDocument=json.dumps(policy),
            Description=description,
        )
    elif len(policy["Statement"]) > 0:
        iam_client.create_policy(PolicyName=policy_name, PolicyDocument=json.dumps(policy))
    result = {
        "FunctionName": function,
        "Qualifier": qualifier,
        "StatementId": statement,
    }
    return jsonify(result)
@app.route("%s/functions/<function>/policy" % API_PATH_ROOT, methods=["GET"])
def get_policy(function):
    qualifier = request.args.get("Qualifier")
    policy = get_lambda_policy(function, qualifier)
    if not policy:
        return not_found_error("The resource you requested does not exist.")