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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)

...

normal_queue_name = 'queue-%s' % short_uid()
        dlq_name = 'queue-%s' % short_uid()
        dlq = self.client.create_queue(QueueName=dlq_name)
        dlq_arn = aws_stack.sqs_queue_arn(dlq_name)
        attributes = {'RedrivePolicy': json.dumps({'deadLetterTargetArn': dlq_arn, 'maxReceiveCount': 100})}
        nq = self.client.create_queue(QueueName=normal_queue_name, Attributes=attributes)['QueueUrl']
        res = self.client.list_dead_letter_source_queues(QueueUrl=dlq['QueueUrl'])
        self.assertEqual(res['queueUrls'][0], nq)
        self.assertEqual(res['ResponseMetadata']['HTTPStatusCode'], 200)
        self.assertEqual(res['queueUrls'][0], nq)
        self.assertEqual(len(res['queueUrls']), 1)
        self.assertEqual(res['ResponseMetadata']['HTTPStatusCode'], 200)
        
        self.client.delete_queue(QueueUrl=nq)
        self.client.delete_queue(QueueUrl=dlq['QueueUrl'])
    def test_lambda_invoked_by_sqs_message_with_attributes(self):
        function_name = 'lambda_func-{}'.format(short_uid())