### 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_
topic_arn = sns_create_topic()["TopicArn"]
        # P
        rs = sns_client.publish(TopicArn=topic_arn, Message=json.dumps({"message": "test_publish"}))
        snapshot.match("response-without-subject", rs)
        assert rs["ResponseMetadata"]["HTTPStatusCode"] == 200
        with pytest.raises(ClientError) as e:
            sns_client.publish(
                TopicArn=topic_arn,
                Subject="",
                Message=json.dumps({"message": "test_publish"}),
            )
        snapshot.match("response-with-empty-subject", e.value.response)
    @pytest.mark.aws_validated
    def test_create_topic_test_arn(self, sns_create_topic, sns_client, snapshot):
        topic_name = "topic-test-create"
        response = sns_create_topic(Name=topic_name)
        snapshot.match("create-topic", response)
        topic_arn_params = response["TopicArn"].split(":")
        testutil.response_arn_matches_partition(sns_client, response["TopicArn"])
        # w
        assert topic_arn_params[5] == topic_name
        if not is_aws_cloud():
            assert topic_arn_params[4] == get_aws_account_id()
    @pytest.mark.aws_validated
    def test_publish_message_by_target_arn(