fix tests

packages/in_app_purchase/test/billing_client_wrappers/billing_client_wrapper_test.dart

@@ -23,6 +23,7 @@ void main() {
 
   setUp(() {
     billingClient = BillingClient((PurchasesResultWrapper _) {});
+    billingClient.enablePendingPurchases();
     stubPlatform.reset();
   });
 
@@ -72,7 +73,7 @@ void main() {
       );
       await billingClient.startConnection(onBillingServiceDisconnected: () {});
       final MethodCall call = stubPlatform.previousCallMatching(methodName);
-      expect(call.arguments, equals(<dynamic, dynamic>{'handle': 0}));
+      expect(call.arguments, equals(<dynamic, dynamic>{'handle': 0, 'enablePendingPurchases': true}));
     });
   });