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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)

...

import os
import re
import glob
import json
import time
import logging
import threading
import subprocess
import six
from multiprocessing import Process, Queue
try:
    from shlex import quote as cmd_quote
except ImportError:
    from pipes import quote as cmd_quote  
from localstack import config
from localstack.utils import bootstrap
from localstack.utils.common import (
    CaptureOutput, FuncThread, TMP_FILES, short_uid, save_file, rm_rf, in_docker,
    to_str, run, cp_r, json_safe, get_free_tcp_port)
from localstack.services.install import INSTALL_PATH_LOCALSTACK_FAT_JAR
from localstack.utils.aws.dead_letter_queue import lambda_error_to_dead_letter_queue, sqs_error_to_dead_letter_queue
from localstack.utils.cloudwatch.cloudwatch_util import store_cloudwatch_logs, cloudwatched
LAMBDA_EXECUTOR_JAR = INSTALL_PATH_LOCALSTACK_FAT_JAR