Update ExtendableTrait.php get_parent_class function to remove deprec…

[theshado40]

Php 8.3 introduced an deprecation error on the get_parent_class function.

[daftspunk]

Thanks!

[daftspunk]

This change looked safe as houses, but since $this referred to static::class when PHP internally used self::class. This produced an error since the static class had a parent, but the class implementing the trait had none.

PHP should add this to their upgrade guide or something:

• get_parent_class() is equivalent to get_parent_class(self::class)

[daftspunk]

Retry fix here: a9566ca

Tests fine over here, need another PHP 8.3 user to confirm .

[Eoler]

Retry fix here: a9566ca
Tests fine over here, need another PHP 8.3 user to confirm .

Yes, that one works for me in PHPv8.2+