Update docs for array-notation routes

[ddrv]

Update docs for slimphp/Slim#3069

[odan]

Hi @ddrv

I'm not sure if this is really officially supported by Slim.

When I try this:

$app->get('/', [\App\Action\Home\HomeAction::class, '__invoke']);

I get this error message because is_callable return false:

App\Action\Home\HomeAction, __invoke is not resolvable in
 vendor\slim\slim\Slim\CallableResolver.php on line 165

This is because is_callable requires an object instead.

Demo: https://3v4l.org/vUN3m

https://www.php.net/manual/en/function.is-callable.php

Edit: I just saw your other PR a little to late.

[ddrv]

@odan Hi!

I send this Pull Request to update the docs after merging the Pull Request to framework code . I should have said this in the description, sorry

[l0gicgate]

@odan this feature will be upcoming in 4.8 see slimphp/Slim#3069

[odan]

@l0gicgate Yes, I just noticed that after I wrote my comment 😄