### Is there an existing issue for this?

- [X] I have searched the existing issues

### Feature description

I would like to request extending `sns_listener` with an ability to understand `email-json` next to `email` protocol.

### 🧑‍💻 Implementation

1. check if protocol is `email` or `email-json`
2. for email json interpret body/message as json

### Anything else?

_No response_
"https",
    "email",
    "email-json",
    "sms",
    "sqs",
    "application",
    "lambda",
    "firehose",
]
class SNSBackend(RegionBackend):
    
    sns_subscriptions: Dict[str, List[Dict]]
    
    subscription_status: Dict[str, Dict]
    
    sns_tags: Dict[str, List[Dict]]
    
    platform_endpoint_messages: Dict[str, List[Dict]]
    
    sms_messages: List[Dict]
    def __init__(self):
        self.sns_subscriptions = {}
        self.subscription_status = {}
        self.sns_tags = {}
        self.platform_endpoint_messages = {}
        self.sms_messages = []
class ProxyListenerSNS(PersistingProxyListener):
    def api_name(self):
        return "sns"
    def forward_request(self, method, path, data, headers):