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# Type of request: This is a ...

[x] bug report
[ ] feature request

# Detailed description

In the `ReceiveMessageResult` of the SQS service, I saw this XML from localstack:

```
...
<MessageAttribute>
     <Name>encoding</Name>
    <Value>
        <DataType>String</DataType>
        <StringValue><![CDATA[gzip]]></StringValue>
    </Value>
</MessageAttribute>
...
```

The `<![CDATA[gzip]]>` is slightly different from AWS, which doesn't wrap the value in a `<!CDATA[[]]>` section. This shouldn't be a problem for XML parsers that accept both plain characters and CDATA sections for this element, but the XML parser I was using did not, which causes an error when running the code against localstack but not when running the code against AWS. There is obviously a bug in the XML parser as well, but I thought that I should at least post this here since it is different than what AWS SQS does.

## Expected behavior

MessageAttribute::Value elements should not be wrapped in `CDATA` sections.

## Actual behavior

MessageAttribute::Value elements all seem to be wrapped in `CDATA` sections.

# Steps to reproduce

Send a message to the SQS service which contains some custom message attributes, then make a ReceiveMessageRequest.

## Command used to start LocalStack

`docker run --env "SERVICES=sqs" localstack/localstack`

## Client code (AWS SDK code snippet, or sequence of "awslocal" commands)

...

global DOCKER_MAIN_CONTAINER_IP
    if DOCKER_MAIN_CONTAINER_IP is None:
        DOCKER_MAIN_CONTAINER_IP = False
        try:
            if in_docker():
                DOCKER_MAIN_CONTAINER_IP = bootstrap.get_main_container_ip()
        except Exception as e:
            LOG.info('Unable to get IP address of main Docker container "%s": %s' %
                (bootstrap.MAIN_CONTAINER_NAME, e))
    
    return DOCKER_MAIN_CONTAINER_IP or config.DOCKER_HOST_FROM_CONTAINER
class LambdaExecutor(object):
    """ Base class for Lambda executors. Subclasses must overwrite the _execute method """
    def __init__(self):
        
        self.function_invoke_times = {}
    def execute(self, func_arn, func_details, event, context=None, version=None,
            asynchronous=False, callback=None):
        def do_execute(*args):
            @cloudwatched('lambda')
            def _run(func_arn=None):
                
                invocation_time = int(time.time() * 1000)
                
                raised_error = None
                result = None
                dlq_sent = None