Fix breaking change - Revert "[11.x] Replace string class names with ::class constants"

[SanderMuller]

Reverts #54134

fixed #54184

@taylorotwell I think this is a breaking change on the old route namespacing eg

Route::namespace('Admin')

    ->group(function (): void {

        Route::view('dashboard', 'admin.dashboard');

    });

this now throws Invalid route action: [App\Http\Controllers\Admin\Illuminate\Routing\ViewController]. because the namespace in this PR was changed from \Illuminate\Routing\ViewController to Illuminate\Routing\ViewController I think.

[SanderMuller]

The same test change has been added in #54186 which shows that the added test fails on the 11.x branch but not in this revert PR with regression test

[shaedrich]

Suggested change

	'\Illuminate\Routing\RedirectController',
	'\Illuminate\Routing\ViewController',
	'\\' . Illuminate\Routing\RedirectController::class,
	'\\' . Illuminate\Routing\ViewController::class,

probably isn't much better, is it?