Update to reflect the fact that react-router has loading states now

[danielnixon]

Historically, when you subscribed to navigation events from React Router, you received one event every time a navigation completed.

Somewhere along the way (v6?), they introduced loading states. See https://reactrouter.com/en/main/route/loader and https://reactrouter.com/en/main/hooks/use-navigation#navigationstate.

Other oaf-routing implementations have handled this by simply ignoring the loading states - in those cases we don't want to announce navigation to screen reader users, update page title, repair focus or restore scroll position.

Here's one example: https://github.com/oaf-project/oaf-navi/blob/master/src/index.ts#L58

We'll need to do the same here.