[consumption] Add ability to change process exit status from within queue consumer extension

[greblov]

<?php
use Enqueue\Consumption\QueueConsumer;
use Enqueue\Consumption\Extension\ExitStatusExtension;

$exitStatusExtension = new ExitStatusExtension();

$fooExtension = new class implements StartExtensionInterface {
    public function onStart(Start $context) 
    {
        $context->interruptExecution(1); // set custom exit code
    }
}

/** @var QueueConsumer $consumer **/
$consumer->consume(new ChainExtension([
    $fooExtension
    $exitStatusExtension
]));

exit($exitStatusExtension->getExitStatus());

[makasim]

no need for this

[makasim]

there is another consume command that has to be adjusted too
you should add a test for command too.

[makasim]

ExitStatusExtension

[makasim]

fixes #759