[12.x] Allow passing an enum to Builder::orderBy()

[cosmastech]

At work, we have three or four separate projects, each which has a SortDirection enum. We use the enum to validate against in HTTP requests, but always have to remember to add ->value when sorting, eg) Athlete::query()->orderBy('last_name', $request->sort->direction->value).

I believe it is a mathematical impossibility that we are the only folks who have this issue. This is certainly not broken as-is, just adding a small quality of life improvement for improved DX.

[shaedrich]

I wonder if Laravel should provide said hypothetical enum rather than letting every implementation provide their own since the available options are quite clear.

[taylorotwell]

I feel like if we keep going down this path every method in the framework that accepts a string will have to accept an enum. 🙃