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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)

...

host = headers.get('host', '')
        headers[HEADER_LOCALSTACK_EDGE_URL] = 'https://%s' % host
        
        api, port, path, host = get_api_from_headers(headers, path)
        if port and int(port) < 0:
            return 404
        if not port:
            port = get_port_from_custom_rules(method, path, data, headers) or port
        if not port:
            if api in ['', None, '_unknown_']:
                truncated = truncate(data)
                LOG.info(('Unable to find forwarding rule for host "%s", path "%s", '
                    'target header "%s", auth header "%s", data "%s"') % (host, path, target, auth_header, truncated))
            else:
                LOG.info(('Unable to determine forwarding port for API "%s" - please '
                    'make sure this API is enabled via the SERVICES configuration') % api)
            response = Response()
            response.status_code = 404
            response._content = '{"status": "running"}'
            return response
        use_ssl = config.USE_SSL
        connect_host = '%s:%s' % (config.HOSTNAME, port)
        url = 'http%s://%s%s' % ('s' if use_ssl else '', connect_host, path)
        headers['Host'] = host
        function = getattr(requests, method.lower())
        if isinstance(data, dict):
            data = json.dumps(data)
        response = function(url, data=data, headers=headers, verify=False)
        return response
def get_api_from_headers(headers, path=None):