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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)

...

sys.stdout, sys.stderr, sys.__stdout__, sys.__stderr__ = (out, err, __out, __err)
    def _proxy(self, original_stream, type):
        def proxy():
            ident = self._ident()
            ctx = self.CONTEXTS_BY_THREAD.get(ident)
            if ctx:
                return ctx._stdout if type == 'stdout' else ctx._stderr
            return original_stream
        return proxy
    def _ident(self):
        return threading.currentThread().ident
    def stdout(self):
        return self._stream_value(self._stdout)
    def stderr(self):
        return self._stream_value(self._stderr)
    def _stream_value(self, stream):
        return stream.getvalue() if hasattr(stream, 'getvalue') else stream
def start_thread(method, *args, **kwargs):
    thread = FuncThread(method, *args, **kwargs)
    thread.start()
    TMP_THREADS.append(thread)
    return thread
def synchronized(lock=None):