Fix for the use of built-in class names in Collection annotations

[27pchrisl]

Hi, found this when upgrading from v3 to v4.

In v3 you could do

#[DataCollectionOf(Error::class)]

which would correctly pick up a class with the right namespace, even if its basename matches a builtin like \Error.

In v4 the same syntax is:

/** @var Collection<Error> */
public Collection $errors;

But due to the order in which the DataIterableAnnotationReader determines the correct class, it discovers \Error before App\Stuff\Error or similar.

This PR reorders the resolution code so that it finds properly qualified classes before builtins.

[27pchrisl]

Note this branch needs rebasing when tests pass again on main

[rubenvanassche]

Looking great, thanks!