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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)

...

""" Determine backend port based on custom rules. """
    
    if 'AWSAccessKeyId=' in path or 'Signature=' in path:
        return config.PORT_S3
    
    if is_sqs_queue_url(path):
        return config.PORT_SQS
    data_bytes = to_bytes(data or '')
    if path == '/' and to_bytes('QueueName=') in data_bytes:
        return config.PORT_SQS
    
    stripped = path.strip('/')
    if method in ['GET', 'HEAD'] and '/' in stripped:
        
        return config.PORT_S3
    if stripped and '/' not in stripped:
        if method == 'PUT':
            
            return config.PORT_S3
        if method == 'POST' and is_s3_form_data(data_bytes):
            
            return config.PORT_S3
def get_service_port_for_account(service, headers):