PHP 8.0 build fails because of symfony/process CVE 2024-51736

[cweiske]

The PHP 8.0 build fails because GrumPHP task "securitychecker_enlightn" fails, e.g. in the cache PR #157:

[CRITICAL] 1 package has known vulnerabilities

symfony/process (6.0.19)
------------------------

 * CVE-2024-51736: CVE-2024-51736: Command execution hijack on Windows with Process class
   https://symfony.com/cve-2024-51736

The symfony CVE got fixed in Symfony 5.4.46, 6.4.14, and 7.1.7.

6.4 is not compatible with PHP 8.0, so the older 6.0.19 package gets installed, which still has the bug.
Also, the symfony patch cannot be simply cherry-picked as there are many conflicts.

I see the following options:

1. Disable GrumPHP security checker
2. Drop support for PHP 8.0 in aus_driver_amazon_s3