Fix upsert billing (#24)

This commit updates the product_id and variant_id in both the subscription_items and order_items in the billing tests. Updates also include adding new checks to verify these changes. Changes are reflected in corresponding SQL files for personal and team billing subscriptions/orders tests.

packages/billing/stripe/src/services/stripe-billing-strategy.service.ts

@@ -123,10 +123,10 @@ export class StripeBillingStrategyService
           ...ctx,
           error,
         },
-        'Failed to cancel subscription',
+        'Failed to cancel subscription. It may have already been cancelled.',
       );
 
-      throw new Error('Failed to cancel subscription');
+      return { success: false };
     }
   }