Deprecation Warnings with v2 and php 8.0

[tolry]

Describe the bug

php 8.0 deprecated libxml_disable_entity_loader since it's no longer needed with the updated libxml version used

To Reproduce

Run version 2.x with deprecation activated (e.g. error_reporting(-1);)

Expected behavior

Getting no deprecation warnings.

Your Environment

• Which version of this library are you using? 2.12.22
• Which version of php are you using? 8.0.11

I have a fix ready here and could submit this, if wanted.

[pabloolvcastro]

I was wondering when this would get fixed. We are currently facing some problems with classes that implement basic PHP interfaces, and the return type has changed in PHP 8. e.g. Recurly_Pager (pager.php) and the interface Iterator. We are running the library version 2.12.37.