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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:
        with tempfile.NamedTemporaryFile() as tf:
            tf.write(content)
            tf.flush()
            with zipfile.ZipFile(tf.name, 'r') as zf:
                jar_entries = [e for e in zf.infolist() if e.filename.lower().endswith('.jar')]
                if match_single_jar and len(jar_entries) == 1 and len(zf.infolist()) == 1:
                    return True
                matching_prefix = [e for e in jar_entries if
                    not jar_path_prefix or e.filename.lower().startswith(jar_path_prefix)]
                return len(matching_prefix) > 0
    except Exception:
        return False
def is_jar_archive(content):
    """ Determine whether `content` contains valid zip bytes representing a JAR archive
        that contains at least one *.class file and a META-INF/MANIFEST.MF file. """
    try:
        with tempfile.NamedTemporaryFile() as tf:
            tf.write(content)
            tf.flush()
            with zipfile.ZipFile(tf.name, 'r') as zf:
                class_files = [e for e in zf.infolist() if e.filename.endswith('.class')]
                manifest_file = [e for e in zf.infolist() if e.filename.upper() == 'META-INF/MANIFEST.MF']
                if not class_files or not manifest_file:
                    return False
    except Exception:
        return False
    return True
def is_root():