static NullPointerException newNullResultException(Authorizer<?> authorizer) {
        return new NullPointerException("A future returned by an " + Authorizer.class.getSimpleName() +
                                        " has been fulfilled with null: " + authorizer);
    }
Determines if the specified {@code data} is authorized for this service. If the result resolves
to {@code true}, the request is authorized, or {@code false} otherwise. If the future resolves
exceptionally, the request will not be authorized.
core/src/main/java/com/linecorp/armeria/server/auth/AuthorizerUtil.java