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# Type of request: This is a ...
[x] bug report
[ ] feature request

# Detailed description
Currently when using [software.amazon.awssdk:kinesis:2.15.27](https://search.maven.org/artifact/software.amazon.awssdk/kinesis/2.15.27/jar) and attempting to use [getRecords](https://sdk.amazonaws.com/java/api/latest/software/amazon/awssdk/services/kinesis/KinesisAsyncClient.html#getRecords-java.util.function.Consumer-) we end up getting a general aws client exception `software.amazon.awssdk.core.exception.SdkClientException: Unable to parse date : 1.605283809962E9`. This doesn't happen when using a live kinesis stream.

## Expected behavior
Should be able to get a response from localstack with the correct data.

## Actual behavior
An exception is thrown from inside aws sdk v2 with the message `software.amazon.awssdk.core.exception.SdkClientException: Unable to parse date : 1.605283809962E9`.

# Steps to reproduce
## Command used to start LocalStack
`docker run -d -p 4566:4566 -e "SERVICES=kinesis" localstack/localstack:0.12.2`

## Client code (AWS SDK code snippet, or sequence of "awslocal" commands)
https://github.com/lukecollier/localstack-jvm-aws-sdk-v2



┆Issue is synchronized with this [Jira Task](https://localstack.atlassian.net/browse/LOC-53) by [Unito](https://www.unito.io/learn-more)

stream_arn = data.get('StreamARN')
                cons_name = data.get('ConsumerName')
                cons_arn = data.get('ConsumerARN')
                return (c.get('ConsumerARN') == cons_arn or
                    (c.get('StreamARN') == stream_arn and c.get('ConsumerName') == cons_name))
            STREAM_CONSUMERS = [c for c in STREAM_CONSUMERS if not consumer_matches(c)]
            return {}
        elif action == 'ListStreamConsumers':
            result = {
                'Consumers': [c for c in STREAM_CONSUMERS if c.get('StreamARN') == data.get('StreamARN')]
            }
            return result
        elif action == 'DescribeStreamConsumer':
            consumer_arn = data.get('ConsumerARN') or data['ConsumerName']
            consumer_name = data.get('ConsumerName') or data['ConsumerARN']
            creation_timestamp = data.get('ConsumerCreationTimestamp')
            result = {
                'ConsumerDescription': {
                    'ConsumerARN': consumer_arn,
                    'ConsumerCreationTimestamp': creation_timestamp,
                    'ConsumerName': consumer_name,
                    'ConsumerStatus': 'ACTIVE',
                    'StreamARN': data.get('StreamARN')
                }
            }
            return result
        if random.random() < config.KINESIS_ERROR_PROBABILITY:
            action = headers.get('X-Amz-Target')
            if action in [ACTION_PUT_RECORD, ACTION_PUT_RECORDS]:
                return kinesis_error_response(data, action)