### 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
]
}
""".strip()
@pytest.fixture
def create_lambda_function(lambda_client, logs_client, iam_client, wait_until_lambda_ready):
    lambda_arns = []
    role_names_policy_arns = []
    log_groups = []
    def _create_lambda_function(*args, **kwargs):
        kwargs["client"] = lambda_client
        func_name = kwargs.get("func_name")
        assert func_name
        del kwargs["func_name"]
        if not kwargs.get("role"):
            role_name = f"lambda-autogenerated-{short_uid()}"
            role = iam_client.create_role(
                RoleName=role_name, AssumeRolePolicyDocument=role_assume_policy
            )["Role"]
            policy_name = f"lambda-autogenerated-{short_uid()}"
            policy_arn = iam_client.create_policy(
                PolicyName=policy_name, PolicyDocument=role_policy
            )["Policy"]["Arn"]
            role_names_policy_arns.append((role_name, policy_arn))
            iam_client.attach_role_policy(RoleName=role_name, PolicyArn=policy_arn)
            kwargs["role"] = role["Arn"]
        def _create_function():
            resp = testutil.create_lambda_function(func_name, **kwargs)
            lambda_arns.append(resp["CreateFunctionResponse"]["FunctionArn"])
            wait_until_lambda_ready(function_name=func_name)
            log_group_name = f"/aws/lambda/{func_name}"