Change PHP template for PHP 8

Changes:

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 to the PHP extensions
being installed: Oniguruma and Zip

Testing:

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

Changelog: fixed

lib/gitlab/ci/templates/PHP.gitlab-ci.yml

@@ -8,9 +8,9 @@ cache:
 
 before_script:
   - apt-get update -yqq
-  - apt-get install -yqq git libmcrypt-dev libpq-dev libcurl4-gnutls-dev libicu-dev libvpx-dev libjpeg-dev libpng-dev libxpm-dev zlib1g-dev libfreetype6-dev libxml2-dev libexpat1-dev libbz2-dev libgmp3-dev libldap2-dev unixodbc-dev libsqlite3-dev libaspell-dev libsnmp-dev libpcre3-dev libtidy-dev
+  - apt-get install -yqq git libpq-dev libcurl4-gnutls-dev libicu-dev libvpx-dev libjpeg-dev libpng-dev libxpm-dev zlib1g-dev libfreetype6-dev libxml2-dev libexpat1-dev libbz2-dev libgmp3-dev libldap2-dev unixodbc-dev libsqlite3-dev libaspell-dev libsnmp-dev libpcre3-dev libtidy-dev libonig-dev libzip-dev
   # Install PHP extensions
-  - docker-php-ext-install mbstring mcrypt pdo_pgsql curl json intl gd xml zip bz2 opcache
+  - docker-php-ext-install mbstring pdo_pgsql curl intl gd xml zip bz2 opcache
   # Install & enable Xdebug for code coverage reports
   - pecl install xdebug
   - docker-php-ext-enable xdebug