### 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_
}
            if message_context.type != "SubscriptionConfirmation":
                
                message_headers["x-amz-sns-subscription-arn"] = subscriber["SubscriptionArn"]
            
            
            
            elif message_context.type == "Notification" and is_raw_message_delivery(subscriber):
                message_headers["x-amz-sns-rawdelivery"] = "true"
            response = requests.post(
                subscriber["Endpoint"],
                headers=message_headers,
                data=message_body,
                verify=False,
            )
            delivery = {
                "statusCode": response.status_code,
                "providerResponse": response.content.decode("utf-8"),
            }
            store_delivery_log(message_context, subscriber, success=True, delivery=delivery)
            response.raise_for_status()
        except Exception as exc:
            LOG.info(
                "Received error on sending SNS message, putting to DLQ (if configured): %s", exc
            )
            store_delivery_log(message_context, subscriber, success=False)
            
            if message_context.type != "UnsubscribeConfirmation":
                sns_error_to_dead_letter_queue(subscriber, message_body, str(exc))
class EmailJsonTopicPublisher(TopicPublisher):