PHP version support

[fruitl00p]

Currently the supported version of PHP in composer.json states "^7.3|^8.0|^8.1" But in the 1.x branch in src/Traits/Helpers.php there's a trailing , in the runProcessInBlast which is only supported since PHP8+
As 7.3 is already was past its EOL, I'd like to propose and drop EOL versions (which does require a semver major bump)

What are your thoughts? It would currently break on PHP7 anyway, and i'd like to contribute some PHP8+ cleanup (return types, property types et al)