### 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_
key = "mock_server_key"
        token = "mock_token"
        response = sns_create_platform_application(
            Name="firebase", Platform="GCM", Attributes={"PlatformCredential": key}
        )
        platform_app_arn = response["PlatformApplicationArn"]
        response = sns_client.create_platform_endpoint(
            PlatformApplicationArn=platform_app_arn,
            Token=token,
        )
        endpoint_arn = response["EndpointArn"]
        message = {
            "GCM": '{ "notification": {"title": "Title of notification", "body": "It works" } }'
        }
        with pytest.raises(ClientError) as ex:
            sns_client.publish(
                TargetArn=endpoint_arn, MessageStructure="json", Message=json.dumps(message)
            )
        assert ex.value.response["Error"]["Code"] == "InvalidParameter"
    @pytest.mark.aws_validated
    @pytest.mark.skip_snapshot_verify(paths=["$..Attributes.SubscriptionPrincipal"])
    def test_subscription_after_failure_to_deliver(
        self,
        sns_client,
        sqs_client,
        sns_create_topic,
        sqs_create_queue,