Auto fix generates broken code

[nickvergessen]

Deps say the lib supports PHP 7.3+
https://github.com/nextcloud/coding-standard/blob/master/composer.json#L6

But the rule for trailing commas on argument lists is 8.0 and creates a parsing error in 7.3 and 7.4

Either the rules needs to be done conditionally or we need to bump the requirement.