### 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_
continue
                messages_amount = len(filtered_messages)
                if messages_amount != messages_amount_before_filtering:
                    LOG.debug(
                        "After applying subscription filter, %s out of %s message(s) to be sent to '%s'",
                        messages_amount,
                        messages_amount_before_filtering,
                        subscriber["SubscriptionArn"],
                    )
                    
                    
                    subscriber_ctx = copy.copy(ctx)
                    subscriber_ctx.messages = filtered_messages
                LOG.debug(
                    "Topic '%s' batch publishing %s messages to subscribed '%s' with protocol '%s' (subscription '%s')",
                    topic_arn,
                    messages_amount,
                    subscriber.get("Endpoint"),
                    subscriber["Protocol"],
                    subscriber["SubscriptionArn"],
                )
                self.executor.submit(
                    notifier.publish, context=subscriber_ctx, subscriber=subscriber
                )
            else:
                
                notifier = self.topic_notifiers[subscriber["Protocol"]]
                for message in ctx.messages:
                    if self._should_publish(
                        ctx.store.subscription_filter_policy, message, subscriber