Use MaterialPageRoute for all platforms when using TransitionType.native

lib/src/fluro_router.dart

@@ -164,23 +164,13 @@ class FluroRouter {
       bool isNativeTransition = (transition == TransitionType.native ||
           transition == TransitionType.nativeModal);
       if (isNativeTransition) {
-        if (Theme.of(buildContext).platform == TargetPlatform.iOS) {
-          return CupertinoPageRoute<dynamic>(
-              settings: routeSettings,
-              fullscreenDialog: transition == TransitionType.nativeModal,
-              maintainState: maintainState,
-              builder: (BuildContext context) {
-                return handler.handlerFunc(context, parameters);
-              });
-        } else {
-          return MaterialPageRoute<dynamic>(
-              settings: routeSettings,
-              fullscreenDialog: transition == TransitionType.nativeModal,
-              maintainState: maintainState,
-              builder: (BuildContext context) {
-                return handler.handlerFunc(context, parameters);
-              });
-        }
+        return MaterialPageRoute<dynamic>(
+            settings: routeSettings,
+            fullscreenDialog: transition == TransitionType.nativeModal,
+            maintainState: maintainState,
+            builder: (BuildContext context) {
+              return handler.handlerFunc(context, parameters);
+            });
       } else if (transition == TransitionType.material ||
           transition == TransitionType.materialFullScreenDialog) {
         return MaterialPageRoute<dynamic>(