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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)

...

try:
                    if port == 53:
                        dnshost = '127.0.0.1' if host == 'localhost' else host
                        resolver = dns.resolver.Resolver()
                        resolver.nameservers = [dnshost]
                        resolver.timeout = 1
                        resolver.lifetime = 1
                        answers = resolver.query('google.com', 'A')
                        assert len(answers) > 0
                    else:
                        sock.sendto(bytes(), (host, port))
                        sock.recvfrom(1024)
                except Exception:
                    return False
            elif nw_protocol == socket.SOCK_STREAM:
                result = sock.connect_ex((host, port))
                if result != 0:
                    return False
    if 'tcp' not in protocols or not http_path:
        return True
    url = '%s://%s:%s%s' % (protocol, host, port, http_path)
    try:
        response = safe_requests.get(url, verify=False)
        return not expect_success or response.status_code < 400
    except Exception:
        return False
def wait_for_port_open(port, http_path=None, expect_success=True, retries=10, sleep_time=0.5):
    """ Ping the given network port until it becomes available (for a given number of retries).
        If 'http_path' is set, make a GET request to this path and assert a non-error response. """
    def check():