[8.x] Add circuit breaker job middleware for unstable services

[paras-malhotra]

It's fairly common to have HTTP calls to third party services in queued jobs. However, some third party services cannot be relied on and may be unstable.

This PR adds a circuit breaker job middleware for such use cases. Once the failures (job exceptions) reach a certain threshold, the circuit breaker trips (circuit opens) and all further calls are delayed until a certain time interval lapses.

To use this job middleware:

use Illuminate\Queue\Middleware\CircuitBreaker;

public function middleware()
{
    return [
        // Trip the circuit after 10 failed attempts in 10 minutes.
        new CircuitBreaker(10, 10),
    ];
}

By default, failed jobs (that don't exceed the threshold) are retried immediately (with an option to specify a delay) and the key for the rate limiter is the class name (with an option to override this to share a key between jobs that may be using the same service).

If this PR is accepted, I'll follow this up with another PR to implement this for Redis using the DurationLimiter.

[taylorotwell]

Do you mind if I rename it to ThrottlesExceptions? Just seems to communicate a bit better what it does from the outside.

[paras-malhotra]

@taylorotwell I borrowed the name from the circuit breaker pattern but I think ThrottlesExceptions conveys the purpose as well.

[taylorotwell]

OK. I have renamed it to ThrottlesExceptions and also added a when method for determining if the exception should be considered a throttable exception by the middleware. If not - it will just re-throw it so the normal exception job handling happens.

public function middleware()
{
    return [
        (new ThrottlesExceptions(5, 1))->when(fn ($e) => $e instanceof SomeException),
    ];
}