fix trackpad not respecting enableSlideVolumeBrightness property

Signed-off-by: dom <githubaccount56556@proton.me>

lib/plugin/pl_player/view/view.dart

@@ -1327,6 +1327,10 @@ class _PLVideoPlayerState extends State<PLVideoPlayer>
         plPlayerController.updatePreviewIndex(newPos ~/ 1000);
       }
     } else if (_gestureType == GestureType.right) {
+      if (!plPlayerController.enableSlideVolumeBrightness) {
+        return;
+      }
+
       final double level = maxHeight * 0.5;
       EasyThrottle.throttle(
         'setVolume',