Integrating Affiliate program into Spark with Stripe Metadata

I can't find any info on how to submit metadata to Stripe when creating the Stripe customer.

I feel like it should be in /src/Interactions/SubscribeTeam.php

(Add ->withMetadata()) but it doesn't work

<?php

namespace Laravel\Spark\Interactions;

use Laravel\Spark\Spark;
use Illuminate\Support\Arr;
use Laravel\Spark\Contracts\Repositories\TeamRepository;
use Laravel\Spark\Events\Teams\Subscription\TeamSubscribed;
use Laravel\Spark\Contracts\Interactions\SubscribeTeam as Contract;

class SubscribeTeam implements Contract
{
    /**
     * {@inheritdoc}
     */
    public function handle($team, $plan, $fromRegistration, array $data)
    {
        $subscription = $team->newSubscription('default', $plan->id);
        $subscription->withMetadata(['property_id' => 'test']);