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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)

...

return json.dumps(obj, sort_keys=True)
def save_file(file, content, append=False):
    mode = 'a' if append else 'w+'
    if not isinstance(content, six.string_types):
        mode = mode + 'b'
    with open(file, mode) as f:
        f.write(content)
        f.flush()
def load_file(file_path, default=None, mode=None):
    if not os.path.isfile(file_path):
        return default
    if not mode:
        mode = 'r'
    with open(file_path, mode) as f:
        result = f.read()
    return result
def to_str(obj, encoding=DEFAULT_ENCODING, errors='strict'):
    """ If ``obj`` is an instance of ``binary_type``, return
    ``obj.decode(encoding, errors)``, otherwise return ``obj`` """
    return obj.decode(encoding, errors) if isinstance(obj, six.binary_type) else obj
def to_bytes(obj, encoding=DEFAULT_ENCODING, errors='strict'):
    """ If ``obj`` is an instance of ``text_type``, return
    ``obj.encode(encoding, errors)``, otherwise return ``obj`` """
    return obj.encode(encoding, errors) if isinstance(obj, six.text_type) else obj
def cleanup(files=True, env=ENV_DEV, quiet=True):
    if files:
        cleanup_tmp_files()
def cleanup_threads_and_processes(quiet=True):