Doesn't support server streaming rpc methods in services

Client has all generated methods as unary methods, I'd expect telescope to generate something different for server streaming rpc methods.

Example of generated streaming method:

```ts
/* StreamCertificates */
streamCertificates = async (request: QueryCertificatesRequest): Promise => {
const data = QueryCertificatesRequest.encode(request).finish();
const promise = this.rpc.request("akash.cert.v1beta3.Query", "StreamCertificates", data);
return promise.then(data => QueryCertificatesResponse.decode(new BinaryReader(data)));
};
```