### 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_
subscriptionARN,
    topicARN,
    topicName,
)
from localstack.http import Request, Response, Router, route
from localstack.services.edge import ROUTER
from localstack.services.moto import call_moto
from localstack.services.plugins import ServiceLifecycleHook
from localstack.services.sns import constants as sns_constants
from localstack.services.sns.models import SnsMessage, SnsStore, SnsSubscription, sns_stores
from localstack.services.sns.publisher import (
    PublishDispatcher,
    SnsBatchPublishContext,
    SnsPublishContext,
)
from localstack.utils.aws import aws_stack
from localstack.utils.aws.arns import parse_arn
from localstack.utils.strings import short_uid
LOG = logging.getLogger(__name__)
class SnsProvider(SnsApi, ServiceLifecycleHook):
    def __init__(self) -> None:
        super().__init__()
        self._publisher = PublishDispatcher()
    def on_before_stop(self):
        self._publisher.shutdown()
    def on_after_init(self):
        
        register_sns_api_resource(ROUTER)
    @staticmethod
    def get_store() -> SnsStore: