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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)

...

try:
        return event['Records'][0][key]
    except KeyError:
        return None
def is_java_lambda(lambda_details):
    runtime = getattr(lambda_details, 'runtime', lambda_details)
    return runtime in [LAMBDA_RUNTIME_JAVA8, LAMBDA_RUNTIME_JAVA11]
def is_nodejs_runtime(lambda_details):
    runtime = getattr(lambda_details, 'runtime', lambda_details)
    return runtime.startswith('nodejs')
def _store_logs(func_details, log_output, invocation_time=None, container_id=None):
    log_group_name = '/aws/lambda/%s' % func_details.name()
    container_id = container_id or short_uid()
    invocation_time = invocation_time or int(time.time() * 1000)
    invocation_time_secs = int(invocation_time / 1000)
    time_str = time.strftime('%Y/%m/%d', time.gmtime(invocation_time_secs))
    log_stream_name = '%s/[LATEST]%s' % (time_str, container_id)
    return store_cloudwatch_logs(log_group_name, log_stream_name, log_output, invocation_time)
def get_docker_host_from_container():