Resolve "PHP CI template commands need an update for PHP 8"

What does this MR do?

The mcrypt module's use is discouraged since 7.2: https://www.php.net/manual/en/migration72.other-changes.php so it has been removed

The JSON module is included by default now so it does not need to be installed explicitly: https://wiki.php.net/rfc/always_enable_json

Couple more development library dependencies were introduced for the PHP extensions being installed: Oniguruma and Zip

Testing:

Testing was performed manually by running it in a pipeline on GitLab.com

Does this MR meet the acceptance criteria?

Conformity

• I have included changelog trailers, or none are needed. (Does this MR need a changelog?)
• I have self-reviewed this MR per code review guidelines.
• This MR does not harm performance, or I have asked a reviewer to help assess the performance impact. (Merge request performance guidelines)
• I have followed the style guides.

Closes #334635 (closed)