docs: public static void asyncUnimplementedUnaryCall(
        MethodDescriptor<?, ?> methodDescriptor, StreamObserver<?> responseObserver) {
      checkNotNull(methodDescriptor, "methodDescriptor");
      checkNotNull(responseObserver, "responseObserver");
      responseObserver.onError(Status.UNIMPLEMENTED
          .withDescription(String.format("Method %s is unimplemented",
              methodDescriptor.getFullMethodName()))
          .asRuntimeException());
    }