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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: A String[] localstack docker container names for each function.
        """
        with self.docker_container_lock:
            LOG.debug('Getting all lambda containers names.')
            cmd = '%s ps -a --filter="name=localstack_lambda_*" --format "{{.Names}}"' % self._docker_cmd()
            LOG.debug(cmd)
            cmd_result = run(cmd, asynchronous=False, stderr=subprocess.PIPE, outfile=subprocess.PIPE).strip()
            if len(cmd_result) > 0:
                container_names = cmd_result.split('\n')
            else:
                container_names = []
            return container_names
    def destroy_existing_docker_containers(self):
        """
        Stops and/or removes all lambda docker containers for localstack.
        :return: None
        """
        with self.docker_container_lock:
            container_names = self.get_all_container_names()
            LOG.debug('Removing %d containers.' % len(container_names))
            for container_name in container_names:
                cmd = '%s rm -f %s' % (self._docker_cmd(), container_name)
                LOG.debug(cmd)
                run(cmd, asynchronous=False, stderr=subprocess.PIPE, outfile=subprocess.PIPE)
    def get_docker_container_status(self, func_arn):
        """
        Determine the status of a docker container.
        :param func_arn: The ARN of the lambda function.
        :return: 1 If the container is running,
        -1 if the container exists but is not running