Update codestyle to use Pint instead of php-cs-fixer and make PHP 8.1 minimum required version

[Rocksheep]

Description

The codestyle has now been changed to laravel/pint in order to match with our other projects. This also needed the mimium version of PHP to be increased to PHP8.1. This was already planned to be done so I have done it now to speed things up.

Motivation and context

It updates the codestyle to the standards of Laravel and SWIS

How has this been tested?

Has not been tested as it's only codestyle and minimum version bump. This might

Screenshots (if appropriate)

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