Description of the new feature/enhancement

I've been investigating steps that could be taken to simplify the ConGetSet interface, with a view towards merging the AdaptDispatch and TerminalDispatch classes (#3849), and I noticed that the GetConsoleCursorInfo and SetConsoleCursorInfo methods are not actually used anywhere. While it's possible we may need something of similar functionality in the future, we wouldn't want it tied to a conhost-specific structure like CONSOLE_CURSOR_INFO if we're going to share the interface with TerminalDispatch, so I think it's probably best to just nuke them for now.

I also noticed that the SCREEN_INFORMATION::GetScrollingRegion is not used anywhere either. It was originally called from the ScrollRegion function, but that usage was removed in PR #2764, so I definitely think it's safe to delete this one.

Proposed technical implementation details (optional)

If there are no objections, I would like to remove these methods.