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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)

...

try:
        float(s)  
        return True
    except (TypeError, ValueError):
        return False
def is_mac_os():
    return bootstrap.is_mac_os()
def is_linux():
    return bootstrap.is_linux()
def is_alpine():
    try:
        if '_is_alpine_' not in CACHE:
            CACHE['_is_alpine_'] = False
            if not os.path.exists('/etc/issue'):
                return False
            out = to_str(subprocess.check_output('cat /etc/issue', shell=True))
            CACHE['_is_alpine_'] = 'Alpine' in out
    except subprocess.CalledProcessError:
        return False
    return CACHE['_is_alpine_']
def get_arch():
    if is_mac_os():
        return 'osx'
    if is_alpine():
        return 'alpine'
    if is_linux():
        return 'linux'
    raise Exception('Unable to determine system architecture')
def short_uid():