### 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_
with pytest.raises(ClientError) as e:
            sns_client.set_subscription_attributes(
                SubscriptionArn=subscription_arn,
                AttributeName="FilterPolicy",
                AttributeValue=json.dumps(nested_filter_policy),
            )
        snapshot.match("sub-filter-policy-nested-error-too-many-combinations", e.value.response)
        flat_filter_policy = {
            "key_a": ["value_one"],
            "key_b": ["value_two"],
            "key_c": ["value_three"],
            "key_d": ["value_four"],
            "key_e": ["value_five"],
            "key_f": ["value_six"],
        }
        # A 
        with pytest.raises(ClientError) as e:
            sns_client.set_subscription_attributes(
                SubscriptionArn=subscription_arn,
                AttributeName="FilterPolicy",
                AttributeValue=json.dumps(flat_filter_policy),
            )
        snapshot.match("sub-filter-policy-max-attr-keys", e.value.response)
        flat_filter_policy = {"key_a": "value_one"}
        # R
        with pytest.raises(ClientError) as e:
            sns_client.set_subscription_attributes(
                SubscriptionArn=subscription_arn,
                AttributeName="FilterPolicy",
                AttributeValue=json.dumps(flat_filter_policy),