### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

It seems that it is possible to receive sns message in an sqs listener if there is a filterpolicy in place for null value in a message attribute, and a message is being sent without the message attribute.

### Expected Behavior

Don't recieve these type of messages

### How are you starting LocalStack?

With a docker-compose file

### Steps To Reproduce

`sns subscribe --topic-arn "demoTopicArn"  --protocol sqs --notification-endpoint "demoSqsEndpoint" --attributes '{"RawMessageDelivery": "true"}'`
`sns set-subscription-attributes --subscription-arn demoSubsArn --attribute-name FilterPolicy --attribute-value '{"testForNull": [null,{"anything-but": ["notgood"]}]}'`
`sns publish --topic-arn demoTopicArn --message "testforrecieval"`
`sqs receive-message --queue-url  "demoUrl"`

### Environment

```markdown
- OS: macOS 13.6
- LocalStack: 2.2.0
```


### Anything else?

_No response_
}
    
    if not subscriber.get("TopicArn", "").endswith(".fifo"):
        region_name = extract_region_from_arn(subscriber["SubscriptionArn"])
        data.update(
            {
                "SignatureVersion": "1",
                
                
                
                "Signature": "EXAMPLEpH+..",
                "SigningCertURL": f"https://sns.{region_name}.amazonaws.com/SimpleNotificationService-0000000000000000000000.pem",
            }
        )
    else:
        data["SequenceNumber"] = message_context.sequencer_number
    if message_type == "Notification":
        unsubscribe_url = create_unsubscribe_url(external_url, subscriber["SubscriptionArn"])
        data["UnsubscribeURL"] = unsubscribe_url
    elif message_type in ("UnsubscribeConfirmation", "SubscriptionConfirmation"):
        data["Token"] = message_context.token
        data["SubscribeURL"] = create_subscribe_url(
            external_url, subscriber["TopicArn"], message_context.token
        )
    if message_context.subject:
        data["Subject"] = message_context.subject
    if message_context.message_attributes:
        data["MessageAttributes"] = prepare_message_attributes(message_context.message_attributes)
    return json.dumps(data)
def prepare_message_attributes(