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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 asyncio
import logging
import traceback
import h11
from quart import make_response, request, Quart
from quart.app import _cancel_all_tasks
from hypercorn.config import Config
from hypercorn.asyncio import serve
from localstack import config
from localstack.utils.common import TMP_THREADS, FuncThread, load_file
from localstack.utils.http_utils import uses_chunked_encoding
from localstack.utils.async_utils import run_sync, ensure_event_loop
LOG = logging.getLogger(__name__)
HTTP_METHODS = ['GET', 'POST', 'PUT', 'DELETE', 'HEAD', 'OPTIONS', 'PATCH']
def setup_quart_logging():