### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

When you publish a message to SNS without a *body* (e.g. only attributes) it succeeds.

### Expected Behavior

Trying to publish a message without a *body* should fail (at least it does when trying to do this in AWS)

### How are you starting LocalStack?

Custom (please describe below)

### Steps To Reproduce

#### How are you starting localstack (e.g., `bin/localstack` command, arguments, or `docker-compose.yml`)

using Java testcontainers...

#### Client commands (e.g., AWS SDK code snippet, or sequence of "awslocal" commands)

```bash
#!/bin/sh
 
queue_arn=$(awslocal sqs create-queue --queue-name $QUEUE_NAME --output text)
echo "Queue ARN: $queue_arn"

topic_arn=$(awslocal sns create-topic --name $TOPIC_NAME --output text)
echo "Topic ARN: $topic_arn"

subscription_arn=$(awslocal sns subscribe \
    --attributes RawMessageDelivery=true \
    --topic-arn "$topic_arn" \
    --protocol sqs \
    --notification-endpoint "$queue_arn" \
    --output text)
echo "Subscription ARN: $subscription_arn" 
```


### Environment

```markdown
- OS: OSX 11.5.2
- LocalStack: 0.13.0
- Docker Desktop: v20.10.8
```


### Anything else?

_No response_
params = []
    def _create_parameter(**kwargs):
        params.append(kwargs["Name"])
        return ssm_client.put_parameter(**kwargs)
    yield _create_parameter
    for param in params:
        ssm_client.delete_parameter(Name=param)
@pytest.fixture
def create_secret(secretsmanager_client):
    items = []
    def _create_parameter(**kwargs):
        create_response = secretsmanager_client.create_secret(**kwargs)
        items.append(create_response["ARN"])
        return create_response
    yield _create_parameter
    for item in items:
        secretsmanager_client.delete_secret(SecretId=item)
only_localstack = pytest.mark.skipif(
    os.environ.get("TEST_TARGET") == "AWS_CLOUD",
    reason="test only applicable if run against localstack",
)
@pytest.fixture
def tmp_http_server():
    test_port, invocations, proxy = start_http_server()
    yield test_port, invocations, proxy
    proxy.stop()