I have a setup where there is a node.js application that writes to a kinesis stream using putRecords for two items. The kinesis stream feeds a Lambda function that is configured with an eventSourceMapping with a batch size of 1. However, when I debug what the Records Kinesis feeds the lambda for an invocation, I see that the lambda is processing two records. Both of these records are on the same shard and have a sequence number which is pretty close.

The interesting thing is that if I switch the node.js published to use putRecord instead of putRecords, the kinesis records have a slightly farther apart sequence number and the lambda is fed the records individually.

The java code to configure the event source mapping
```
        AWSLambdaAsync lambdaClient = AWSResourceFactory.getLambdaClient();
        CreateEventSourceMappingRequest request = new CreateEventSourceMappingRequest();
        request.setEventSourceArn(kinesisArn);
        request.setFunctionName(functionName);
        request.setEnabled(true);
        request.setStartingPosition(EventSourcePosition.TRIM_HORIZON);
        request.setBatchSize(1);
        lambdaClient.createEventSourceMapping(request);
```

The localstack lambda output that shows multiple records being read at a time:

```
{
	"Records": [{
		"eventID": "shardId-000000000000:49593014281924840790139112603493819506073986345293840386",
		"eventSourceARN": "arn:aws:kinesis:us-east-1:000000000000:stream/MyStream",
		"kinesis": {
			"partitionKey": "ed0f756b97234f4fae9e3d1a886b8fbc",
			"data": "myData1",
			"sequenceNumber": "49593014281924840790139112603493819506073986345293840386"
		}
	}, {
		"eventID": "shardId-000000000000:49593014281924840790139112603495028431893600974468546562",
		"eventSourceARN": "arn:aws:kinesis:us-east-1:000000000000:stream/MyStream",
		"kinesis": {
			"partitionKey": "abee63a9299385699d65e89a290a9065",
			"data": "myData2",
			"sequenceNumber": "49593014281924840790139112603495028431893600974468546562"
		}
	}]
}
```

except Exception as e:
        LOG.warning('Unable to run Lambda function on API Gateway message: %s %s' % (e, traceback.format_exc()))
def process_sns_notification(func_arn, topic_arn, subscriptionArn, message, message_attributes, subject='',):
    try:
        event = {
            'Records': [{
                'EventSource': 'localstack:sns',
                'EventVersion': '1.0',
                'EventSubscriptionArn': subscriptionArn,
                'Sns': {
                    'Type': 'Notification',
                    'TopicArn': topic_arn,
                    'Subject': subject,
                    'Message': message,
                    'Timestamp': timestamp(format=TIMESTAMP_FORMAT_MILLIS),
                    'MessageAttributes': message_attributes
                }
            }]
        }
        return run_lambda(event=event, context={}, func_arn=func_arn, asynchronous=True)
    except Exception as e:
        LOG.warning('Unable to run Lambda function on SNS message: %s %s' % (e, traceback.format_exc()))
def process_kinesis_records(records, stream_name):
    
    try:
        stream_arn = aws_stack.kinesis_stream_arn(stream_name)
        sources = get_event_sources(source_arn=stream_arn)
        for source in sources:
            arn = source['FunctionArn']
            event = {