GetStateAsync throws exception if key not found when using json contentType

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I am using `redis` for state store component with `RedisJSON` module, and when getting state with `contentType` metadata set to `application/json`, method `GetStateAsync` on the dapr client throws the following exception if the key doesn't exist:
```
Error when trying to Retrieve ... with Id: ..."Error","@x":"Dapr.DaprException:
State operation failed: the Dapr endpoint indicated a failure. See InnerException for details.
Grpc.Core.RpcException: Status(StatusCode=\"Internal\", Detail=\"fail to get <...> from state store local: redis: nil\")
at Dapr.Client.DaprClientGrpc.GetStateAsync[TValue](String storeName, String key, Nullable`1 consistencyMode, IReadOnlyDictionary`2 metadata, CancellationToken cancellationToken)
```

Is this an intended behavior or more like a bug? When not using any metadata the return value from `GetStateAsync` is `null` with no exception thrown if the key doesn't exist.

Thanks!