Add support for PHP 8

[kkoumantaros]

Adding support for php8 would be useful as anything bellow 7.2 seems to be EOL

[gregcorbett]

Thanks for this @kkoumantaros, we didn't have a standalone issue to track this - only #337, which is much broader in scope.

I've posted a update in #337 to clarify how the various draft/open PRs fit together to update various parts of the codebase.

Some work has been done to support PHP8: https://github.com/gregcorbett/gocdb/commits/php8/. IIRC, updating to PHP 8 will require us to update the version of PHPUnit we use - which will require some refactoring of the unit tests themselves and the branch php8 gets us some of the way there. I will have to refresh my understanding of the exact situation here.

As Rocky 8 has both module for PHP 7.4 and 8.0 - we may aim to support PHP 8.0+ only, dropping support for PHP 7.4.

[kkoumantaros]

As PHP 7.4 is EOL I would suggest you focus on PHP 8 ...