fix(react): Update types to match react router 6.4 updates

[AbhiPrasad]

Supersedes #5915'
Fixes #5959

Fixes a type mismatch caused by change remix-run/react-router#9366 in react-router code. Have to use any because of typing changes in the above PR, since we can't be backwards compatible with both versions very easily.

[Lms24]

LGTM, out of curiosity, you said that it's not very easy to maintain backwards compatiblity if we didn't use any but a stronger type. What would we need to do to get that stronger type?

Not saying it needs to be done (consider this a logaf extra-l) but since we try to avoid any as much as possible, I was just curious.

[mydea]

L: I guess to reduce duplication this could also be something like:

interface BaseRouteObject {
  caseSensitive?: boolean;
  element?: React.ReactNode | null;
  path?: string;
}

type IndexRouteObject = BaseRouteObject & { index: true, children?: undefined };
type NonIndexRouteObject = BaseRouteObject & { index: false, children?: RouteObject[]; };
type RouteObject = IndexRouteObject | NonIndexRouteObject;

But not sure if it is really worth it, or just adds unnecessary complexity 🤔

[AbhiPrasad]

I just kept the types from what was done in #5915, you're change is cleaner, but I'll just keep it like this for now. We can update this afterwards if we need to.

[AbhiPrasad]

LGTM, out of curiosity, you said that it's not very easy to maintain backwards compatiblity if we didn't use any but a stronger type. What would we need to do to get that stronger type?

The problem here is that with TS 3.8.3, TypeScript isn't smart enough to discriminate the union RouteObject type. There might be a way to make this work, but I figured just slamming any with type casts is good enough. We have plenty of tests for different behavior here, so we should be able to still make this work.