title: stripeRole not syncing to user claims
body: <p>I built a website (React + Firebase), and am now looking to add a paid subscription via Stripe.</p>
  <p>I got this mostly working using the standard add-on (firestore-stripe-payments). Now, my checkout process works, and data from Stripe syncs to my firestore. I can see subscriptions appearing for my users in firestore. After adding <code>stripeRole</code> as metadata for my product in the Stripe dashboard, I can also see the field <code>role</code> in these subscriptions.</p>
  <p>However, I can't figure out how to see the subscription role for the user in the frontend. Following some tutorials, it seems that <code>user.getIdTokenResult()</code> should get me a <code>decodedToken.claims.stripeRole</code>. I can get the <code>decodedToken.claims</code> but it just does not include <code>stripeRole</code>.</p>
  <p>Where should I investigate further? / What should I do differently?</p>