[5.5] Use path helpers for Console commands

[Pascal-So]

When trying to use a custom public path, the Op of issue #18550 was advised to override the path.public binding. I did the same for my application, however I was then unable to use the artisan serve command, because that just uses the hardcoded value in publicPath(), instead of the bindings.

The error message I received was this:

$ php artisan serve
In ServeCommand.php line 35:

  chdir(): No such file or directory (errno 2)

StorageLinkCommand.php already uses the public_path() helper (although with the argument 'storage'), so it seems this commit doesn't introduce a new dependency on these helpers that wasn't there before.

If there was a specific reason to not use these helper functions, maybe we can find some other solution.