[10.x] Allow Listeners to dynamically specify delay using withDelay

[calebdw]

Hello!

There's currently not a way to specify the queued listener delay at runtime like there is with the queue and connection (viaQueue and viaConnection, respectively). This PR allows a listener to define a withDelay method (NotificationSender uses same method name) that can accept the event to adjust the delay based on the event properties.

Example

class Listener implements ShouldQueue
{
    public function __invoke(Event $event): void
    {
        // ...
    }

    public function withDelay(Event $event): int
    {
        return $event->fooBar
            ? <short_delay>
            : <long_delay>;
    }
}

If this PR is accepted then I'll submit a PR to the docs repo.

Thanks!

[calebdw]

Thank you sir!