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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)
```


return 1000 * 60
def cleanup():
    region = LambdaRegion.get()
    region.lambdas = {}
    region.event_source_mappings = []
    LAMBDA_EXECUTOR.cleanup()
def func_arn(function_name, remove_qualifier=True):
    parts = function_name.split(':function:')
    if remove_qualifier and len(parts) > 1:
        function_name = '%s:function:%s' % (parts[0], parts[1].split(':')[0])
    return aws_stack.lambda_function_arn(function_name)
def func_qualifier(function_name, qualifier=None):
    region = LambdaRegion.get()
    arn = aws_stack.lambda_function_arn(function_name)
    details = region.lambdas.get(arn)
    if not details:
        return details
    if details.qualifier_exists(qualifier):
        return '{}:{}'.format(arn, qualifier)
    return arn
def check_batch_size_range(source_arn, batch_size=None):