fix(auth): firestore processor didnt ignore proper errors

Because:

* The firestore processor failed to find existing records for deleted
  customers nor could it create them as we don't store deleted
  customers.

This commit:

* Catches both the stripe customer deleted error and the lack of a
  firestore record from the same error case.

Closes #13591

packages/fxa-auth-server/lib/payments/stripe.ts

@@ -3014,7 +3014,12 @@ export class StripeHelper extends StripeHelperBase {
         }
       }
     } catch (err) {
-      if (err.name === FirestoreStripeError.STRIPE_CUSTOMER_DELETED) {
+      if (
+        [
+          FirestoreStripeError.STRIPE_CUSTOMER_DELETED,
+          FirestoreStripeError.FIRESTORE_CUSTOMER_NOT_FOUND,
+        ].includes(err.name)
+      ) {
         // We cannot back-fill Firestore with records for deleted customers
         // as they're missing necessary metadata for us to know which user
         // the customer belongs to.

packages/fxa-auth-server/test/local/payments/stripe.js

@@ -5916,7 +5916,7 @@ describe('StripeHelper', () => {
       );
     });
 
-    it('ignores the deleted customer error when handling a payment method update event', async () => {
+    it('ignores the deleted stripe customer error when handling a payment method update event', async () => {
       const event = deepCopy(eventPaymentMethodAttached);
       event.type = 'payment_method.card_automatically_updated';
       stripeHelper.stripe.paymentMethods.retrieve = sandbox
@@ -5937,6 +5937,27 @@ describe('StripeHelper', () => {
       );
     });
 
+    it('ignores the firestore record not found error when handling a payment method update event', async () => {
+      const event = deepCopy(eventPaymentMethodAttached);
+      event.type = 'payment_method.card_automatically_updated';
+      stripeHelper.stripe.paymentMethods.retrieve = sandbox
+        .stub()
+        .resolves(event.data.object);
+      stripeFirestore.insertPaymentMethodRecordWithBackfill = sandbox
+        .stub()
+        .throws(
+          newFirestoreStripeError(
+            'Customer deleted.',
+            FirestoreStripeError.FIRESTORE_CUSTOMER_NOT_FOUND
+          )
+        );
+      await stripeHelper.processWebhookEventToFirestore(event);
+      sinon.assert.calledOnceWithExactly(
+        stripeFirestore.insertPaymentMethodRecordWithBackfill,
+        event.data.object
+      );
+    });
+
     it('does not handle wibble events', async () => {
       const event = deepCopy(eventSubscriptionUpdated);
       event.type = 'wibble';