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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)

...

for name in ['quart.app', 'quart.serving']:
        log = logging.getLogger(name)
        log.setLevel(logging.INFO if config.DEBUG else logging.WARNING)
        for hdl in list(log.handlers):
            log.removeHandler(hdl)
def apply_patches():
    def InformationalResponse_init(self, *args, **kwargs):
        if kwargs.get('status_code') == 100 and not kwargs.get('reason'):
            
            kwargs['reason'] = 'Continue'
        InformationalResponse_init_orig(self, *args, **kwargs)
    InformationalResponse_init_orig = h11.InformationalResponse.__init__
    h11.InformationalResponse.__init__ = InformationalResponse_init
def run_server(port, handler=None, asynchronous=True, ssl_creds=None):
    ensure_event_loop()
    app = Quart(__name__)
    @app.route('/', methods=HTTP_METHODS, defaults={'path': ''})
    @app.route('/<path:path>', methods=HTTP_METHODS)
    async def index(path=None):
        response = await make_response('{}')
        if handler:
            data = await request.get_data()
            try:
                result = await run_sync(handler, request, data)
            except Exception as e:
                LOG.warning('Error in proxy handler for request %s %s: %s %s' %
                    (request.method, request.url, e, traceback.format_exc()))