Cannot pan on y-axis when zoomed and rotated=true

Hi All,
in `rotated=true` charts, when you zoom (using type `zoom.type=scroll`, because `zoom.type=drag` doesn't work ) you cannot pan on the `y-axis` to see the others values.

Check the following jsfiddle:
https://jsfiddle.net/yeo0rkwx/
(zoom using the scroll-wheel then drag vertically: the chart won't move, while doing the same when `rotated=false` works for the x-axis).

* **C3 version**: 0.7.18
* **D3 version**: 5.9.2
* **Browser**: Chrome 83.0.4103.116, Firefox 77.0.1
* **OS**: Windows 10