Missing styling documentation for native sidebar

[tieniber]

The documentation discusses the ability to use a sidebar for navigation in a mobile app:

https://docs.mendix.com/refguide/mobile/designing-mobile-user-interfaces/navigation/#sidebar

However, the styling documentation doesn't cover how to style the sidebar. It only talks about the bottom bar:

https://docs.mendix.com/refguide/mobile/designing-mobile-user-interfaces/widget-styling-guide/#navigation-widget