code: public static ServerServiceDefinition interceptForward(ServerServiceDefinition serviceDef,
                                                           ServerInterceptor... interceptors) {
      return interceptForward(serviceDef, Arrays.asList(interceptors));
    }
docs: Create a new {@code ServerServiceDefinition} whose {@link ServerCallHandler}s will call
  {@code interceptors} before calling the pre-existing {@code ServerCallHandler}. The first
  interceptor will have its {@link ServerInterceptor#interceptCall} called first.
  
  @param serviceDef   the service definition for which to intercept all its methods.
  @param interceptors array of interceptors to apply to the service.
  @return a wrapped version of {@code serviceDef} with the interceptors applied.