[PM-14456] Return provider type when getting provider's subscription (#4972)

src/Api/Billing/Controllers/ProviderBillingController.cs

@@ -93,7 +93,8 @@ public class ProviderBillingController(
             subscription,
             providerPlans,
             taxInformation,
-            subscriptionSuspension);
+            subscriptionSuspension,
+            provider);
 
         return TypedResults.Ok(response);
     }