onEnter and onLeave horizontal is triggered on vertical scroll

# Expected Behavior #
onEnter and onLeave are triggered when the component enters and leaves the viewport when the parent div is scrolled horizontally, when prop horizontal is given.
# Current Behavior #
onEnter and onLeave correctly inform if the component is in view, but they are only triggered when the page is scrolled vertically.
# Steps to Reproduce #
Component
```

```
Handlers
```
const _handleWaypointEnter = () => {
setInView(true);
setChangeCount(changeCount + 1);
};
const _handleWaypointLeave = () => {
setInView(false);
setChangeCount(changeCount + 1);
};
```
### React: 17.0.2
### react-waypoint: 9.0.3