### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

I am running an SNS topic that publishes to a lambda function. The localstack code reads a type byte object from the lambda function invocation payload [here](https://github.com/localstack/localstack/blob/master/localstack/services/sns/publisher.py#L187) and then tries to dump the result into json [here](https://github.com/localstack/localstack/blob/master/localstack/services/sns/publisher.py#L863) which results in the following error:
```
sns_pub_0] l.services.sns.publisher   : Unable to run Lambda function on SNS message: Object of type bytes is not JSON serializable
```

### Expected Behavior

The payload bytes should be converted to a string before being dumped to json. The error should not be thrown.

### How are you starting LocalStack?

With a docker-compose file

### Steps To Reproduce

#### How are you starting localstack (e.g., `bin/localstack` command, arguments, or `docker-compose.yml`)

docker-compose up
(Using the standard docker-compose.yaml)

#### Client commands (e.g., AWS SDK code snippet, or sequence of "awslocal" commands)

```
awslocal sns publish --message file://sns/message.json --topic-arn arn:aws:sns:us-east-1:000000000000:<topic_name>
```

### Environment

```markdown
- OS: macOS Ventura 13.2.1
- LocalStack: latest
```


### Anything else?

_No response_
self.executor = ThreadPoolExecutor(num_thread, thread_name_prefix="sns_pub")
    def shutdown(self):
        self.executor.shutdown(wait=False)
    def _should_publish(
        self, store: SnsStore, message_ctx: SnsMessage, subscriber: SnsSubscription
    ):
        """
        Validate that the message should be relayed to the subscriber, depending on the filter policy
        """
        subscriber_arn = subscriber["SubscriptionArn"]
        filter_policy = store.subscription_filter_policy.get(subscriber_arn)
        if not filter_policy:
            return True
        
        match subscriber.get("FilterPolicyScope", "MessageAttributes"):
            case "MessageAttributes":
                return self.subscription_filter.check_filter_policy_on_message_attributes(
                    filter_policy=filter_policy, message_attributes=message_ctx.message_attributes
                )
            case "MessageBody":
                return self.subscription_filter.check_filter_policy_on_message_body(
                    filter_policy=filter_policy,
                    message_body=message_ctx.message_content(subscriber["Protocol"]),
                )
    def publish_to_topic(self, ctx: SnsPublishContext, topic_arn: str) -> None: