[8.x] Allow adding catch callbacks for chains

[themsaid]

This PR add a new Bus::chain() method similar to Bus::batch() and also allows attaching catch callbacks to chain:

Bus::chain([
    new Job(),
    new Job2(),
    new Job3()
])->catch(function ($e) {
    info($e->getMessage());
})->dispatch();

The callbacks will be invoked if any of the jobs fail.

[GrahamCampbell]

I don't think userland code should ever call dynamic methods like that? Can we not just literally invoke it?

(collect($this->chainCatchCallbacks)->each)($e);

[themsaid]

@GrahamCampbell hmmm what's the reason?

[GrahamCampbell]

Magic methods are not meant to be called directly. It's hacky to do that. Just like it's hacky to use reflection to make a private method callable and then call it. Those methods are there to be used by PHP native syntax. __invoke is meant to be called only be actually calling the class and __get is meant to be called only by doing a property access, etc. Obviously, there are exceptions, but I don't think this is one of those cases.