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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)

...

out = run('whoami').strip()
    return out == 'root'
def cleanup_resources():
    cleanup_tmp_files()
    cleanup_threads_and_processes()
@synchronized(lock=SSL_CERT_LOCK)
def generate_ssl_cert(target_file=None, overwrite=False, random=False, return_content=False, serial_number=None):
    
    
    from OpenSSL import crypto
    def all_exist(*files):
        return all([os.path.exists(f) for f in files])
    def store_cert_key_files(base_filename):
        key_file_name = '%s.key' % base_filename
        cert_file_name = '%s.crt' % base_filename
        
        content = load_file(target_file)
        key_start = '-----BEGIN PRIVATE KEY-----'
        key_end = '-----END PRIVATE KEY-----'
        cert_start = '-----BEGIN CERTIFICATE-----'
        cert_end = '-----END CERTIFICATE-----'
        key_content = content[content.index(key_start): content.index(key_end) + len(key_end)]