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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)
```


message_attributes, unsubscribe_url, subject='',):
    event = {
        'Records': [{
            'EventSource': 'localstack:sns',
            'EventVersion': '1.0',
            'EventSubscriptionArn': subscription_arn,
            'Sns': {
                'Type': 'Notification',
                'MessageId': message_id,
                'TopicArn': topic_arn,
                'Subject': subject,
                'Message': message,
                'Timestamp': timestamp_millis(),
                'SignatureVersion': '1',
                
                
                'Signature': 'EXAMPLEpH+..',
                'SigningCertUrl': 'https://sns.us-east-1.amazonaws.com/SimpleNotificationService-000000000.pem',
                'UnsubscribeUrl': unsubscribe_url,
                'MessageAttributes': message_attributes
            }
        }]
    }
    inv_result = run_lambda(func_arn=func_arn, event=event, context={}, asynchronous=not config.SYNCHRONOUS_SNS_EVENTS)
    return inv_result.result
def process_kinesis_records(records, stream_name):
    def chunks(lst, n):
        
        for i in range(0, len(lst), n):
            yield lst[i:i + n]