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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)

...

raise_error = None
    if sleep_before > 0:
        time.sleep(sleep_before)
    for i in range(0, retries + 1):
        try:
            return function(**kwargs)
        except Exception as error:
            raise_error = error
            time.sleep(sleep)
    raise raise_error
def dump_thread_info():
    for t in threading.enumerate():
        print(t)
    print(run("ps aux | grep 'node\\|java\\|python'"))
def merge_recursive(source, destination, none_values=[None]):
    for key, value in source.items():
        if isinstance(value, dict):
            
            node = destination.setdefault(key, {})
            merge_recursive(value, node)
        else:
            if not isinstance(destination, dict):
                LOG.warning('Destination for merging %s=%s is not dict: %s' %
                    (key, value, destination))
            if destination.get(key) in none_values:
                destination[key] = value
    return destination
def merge_dicts(*dicts, **kwargs):