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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)

...

) % (docker_cmd, rm_flag, container_name, mount_volume_str, env_vars_str, network_str, docker_image)
                LOG.debug(cmd)
                run(cmd)
                if not mount_volume:
                    LOG.debug('Copying files to container "%s" from "%s".' % (container_name, lambda_cwd))
                    cmd = (
                        '%s cp'
                        ' "%s/." "%s:/var/task"'
                    ) % (docker_cmd, lambda_cwd, container_name)
                    LOG.debug(cmd)
                    run(cmd)
                LOG.debug('Starting container: %s' % container_name)
                cmd = '%s start %s' % (docker_cmd, container_name)
                LOG.debug(cmd)
                run(cmd)
                
                time.sleep(1)
            
            LOG.debug('Getting the entrypoint for image: %s' % (docker_image))
            cmd = (
                '%s image inspect'
                ' --format="{{ .ContainerConfig.Entrypoint }}"'
                ' %s'
            ) % (docker_cmd, docker_image)
            LOG.debug(cmd)
            run_result = run(cmd)
            entry_point = run_result.strip('[]\n\r ')
            container_network = self.get_docker_container_network(func_arn)
            LOG.debug('Using entrypoint "%s" for container "%s" on network "%s".'
                % (entry_point, container_name, container_network))