[11.x] Add withoutDefer and withDefer testing helpers

[timacdonald]

Adds the ability to have deferred functions execute immediately within a test.

This is useful when you are working with unit tests that cover and assert against deferred function outcomes, as deferred functions are only invoked at the end of the request lifecycle.

User::create(/* ... */);

$this->assertAgainstSomeDeferredOutcome(); // will not work

$this->withoutDefer();

User::create(/* ... */);

$this->assertAgainstSomeDeferredOutcome(); // will now work

[timacdonald]

Docs: laravel/docs#10006

[Sairahcaz]

Maybe it would be nice to have a little helper for that:

function assertAfterDefer(Closure $callback): void
{
    app(DeferredCallbackCollection::class)->invoke();

    $callback();
}

it('sends an api request if a new user gets created', function () {
    User::create([
        'email' => $this->faker->safeEmail(),
        'password' => bcrypt('password'),
    ]);

    assertAfterDefer(fn () => Http::assertSent(function ($request) {
        return $request->url() == $this->apiUrl.'stats-user' && $request->method() == 'POST';
    }));
});