Silverstripe in PHP 8

This project consists of:

• A Dockerfile that generates a PHP 8 + Apache image with necessary extensions built and enabled
• A docker-compose.yml file that spins up the PHP container alongside a MySQL container and links them together
• A Silverstripe CMS 4.x-dev build that points to necessary forks for PHP 8 support whilst it's in development

To run the environment:

cd build
composer install
cd ..
docker-compose up -d --build

The web server will be accessible at http://localhost:8090. To SSH in and run PHPUnit:

docker exec -it silverstripe-php8-env_web_1 /bin/bash

Xdebug 3 is also present and enabled. This works with web requests, but not with CLI commands so far. You may need to disable it to successfully run /dev/build ;)