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# Type of request: This is a ...

[x] bug report
[ ] feature request

# Detailed description
When I call the Lambda PutFunctionEventInvokeConfig API using the aws-java-sdk, the sdk throws an exception claiming it cannot parse the LastModified timestamp in the response:
```
software.amazon.awssdk.core.exception.SdkClientException: Unable to parse date : 2021-05-28T16:02:30.018Z
        at software.amazon.awssdk.core.exception.SdkClientException$BuilderImpl.build(SdkClientException.java:98)
        at software.amazon.awssdk.protocols.core.StringToInstant.lambda$safeParseDate$0(StringToInstant.java:77)
        at software.amazon.awssdk.protocols.core.StringToInstant.convert(StringToInstant.java:54)
        at software.amazon.awssdk.protocols.core.StringToInstant.convert(StringToInstant.java:32)
```

For comparison, the response for a getting a FunctionEventInvokeConfig for a Lambda of a real AWS account using the aws-cli is the following:
```
{
    "LastModified": "2021-05-27T19:26:43.454000-07:00",
    "FunctionArn": "...",
    ...
}
```

## Expected behavior
LambdaAsyncClient in aws-java-sdk should correctly parse the response for a PutFunctionEventInvokeConfig request.

## Actual behavior
LambdaAsyncClient in aws-java-sdk throws an exception when parsing the LastModified field in the response.

# Steps to reproduce

## Command used to start LocalStack
```
docker run -d --rm --name localstack -p 4566:4566 localstack/localstack:latest
```

## Client code (AWS SDK code snippet, or sequence of "awslocal" commands)
```
val putEventInvokeConfigRequest =
  PutFunctionEventInvokeConfigRequest.builder
    .functionName(functionName)
    .maximumEventAgeInSeconds(21600)
    .maximumRetryAttempts(0)
    .build
lambdaClient.putFunctionEventInvokeConfig(putEventInvokeConfigRequest)
```


if error and not dlq_sent:
                
                
                
                return
            sqs_client = aws_stack.connect_to_service('sqs')
            entries = [{'Id': r['receiptHandle'], 'ReceiptHandle': r['receiptHandle']} for r in records]
            try:
                sqs_client.delete_message_batch(QueueUrl=queue_url, Entries=entries)
            except Exception as e:
                LOG.info('Unable to delete Lambda events from SQS queue ' +
                    '(please check SQS visibility timeout settings): %s - %s' % (entries, e))
        records = []
        for msg in messages:
            message_attrs = message_attributes_to_lower(msg.get('MessageAttributes'))
            records.append({
                'body': msg['Body'],
                'receiptHandle': msg['ReceiptHandle'],
                'md5OfBody': msg['MD5OfBody'],
                'eventSourceARN': queue_arn,
                'eventSource': lambda_executors.EVENT_SOURCE_SQS,
                'awsRegion': region,
                'messageId': msg['MessageId'],
                'attributes': msg.get('Attributes', {}),
                'messageAttributes': message_attrs,
                'md5OfMessageAttributes': msg.get('MD5OfMessageAttributes'),
                'sqs': True,
            })
        event = {'Records': records}