Spark 8.0 is a simple maintenance release to provide compatibility with Laravel 5.8 and Cashier 9.0. As such, there are no Spark specific upgrade instructions. You should simply upgrade your application using the Laravel 5.8 upgrade guide. In addition, ensure that your application's composer.json file is requiring Laravel Cashier ^9.0.
If you installed Spark via the spark CLI tool, you may run the spark:update Artisan command:
php artisan spark:update --majorIf you installed Spark via Composer, you may simply upgrade your dependency name and version in your composer.json file and run the composer update command. Of course, in order for your GitHub user to access the repository, you should first join this repository in the Spark dashboard:
"laravel/spark-aurelius": "~8.0"