Update ruleset for modern (PHP 8+) code

[mmoll]

[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 100.00%. Comparing base (93dad05) to head (833c7b6).

Additional details and impacted files

@@             Coverage Diff             @@
##              master      #224   +/-   ##
===========================================
  Coverage     100.00%   100.00%           
  Complexity       147       147           
===========================================
  Files              8         8           
  Lines            669       669           
===========================================
  Hits             669       669           

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[sonarqubecloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[mmoll]

@xalopp please have a look... This is copying over from a ruleset I used on top of MO4 10.x with modern projects, but leaving out a few things like forcing declare(strict_types=1);

[mmoll]

@4d4ch4u32 this will change/improve things for your dependent CS, please also have a look.

[xalopp]

@mmoll looks fine. Because of "breaking" changes (less doc comments requires), this will be a 11.0.x :rocket:

[mmoll]

this will be a 11.0.x 🚀

#216 already is a 11.x 💣