[11.x] Simple scoped bindings container registration

[freerkminnema]

In #37521, Laravel introduced "scoped" binding. This PR adds support for a $scopedBindings property on service providers to allow for the registration of simple scoped bindings. It also has support for tersely binding classes that don't have a backing contract, as was introduced for simple singleton bindings in #43469.

For "regular" bindings and singletons, there already exist convenient properties ($bindings and $singletons respectively), that can be used to simplify registration of bindings.

When using Laravel Octane, you regularly encounter situations where you might want to use a scoped binding, but currently you need to implement the register() method when you want to do this.

Before:

class AppServiceProvider extends ServiceProvider
{
    public array $bindings = [
        ServerProvider::class => DigitalOceanServerProvider::class,
    ];
 
    public array $singletons = [
        DowntimeNotifier::class => PingdomDowntimeNotifier::class,
    ];

    public function register()
    {
        $this->app->scoped(RequestScopedClassContract::class, RequestScopedClass::class)
    }
}

When skimming the code above, it feels like there is a fundamental difference between the different types of bindings.

When looking at the code below, the connection between the three types of bindings is more obvious.

After:

class AppServiceProvider extends ServiceProvider
{
    public array $bindings = [
        ServerProvider::class => DigitalOceanServerProvider::class,
    ];
 
    public array $scopedBindings = [
        RequestScopedClassContract::class => RequestScopedClass::class,
    ];
 
    public array $singletons = [
        DowntimeNotifier::class => PingdomDowntimeNotifier::class,
    ];
}

[taylorotwell]

Thanks for your pull request to Laravel!

Unfortunately, I'm going to delay merging this code for now. To preserve our ability to adequately maintain the framework, we need to be very careful regarding the amount of code we include.

If applicable, please consider releasing your code as a package so that the community can still take advantage of your contributions!