[11.x] Add BackedEnum support to Authorize middleware

[diaafares]

Hi,
Using Enums enhances code readability and reduces typos; it also improves IDE support by providing better autocomplete

After merging this PR #52561
I tried to use BackedEnums with Authorize::using() but it didn't worked:

 Route::get('/dashboard', [AdminDashboardController::class, 'index'])->middleware(Authorize::using(Abilities::VIEW_DASHBOARD))->name(AdminRoutes::DASHBOARD);

This PR adds support for using BackedEnums with Authorize::using()

This PR is backward compatible and shouldn't bring any breaking changes.