Delete MultiRule

[cortinico]

We can finally remove MultiRule as we're not using it anymore.
This is also a breaking change that will be shipped with 2.0.0

Fixes #5192

[codecov]

Codecov Report

Merging #6288 (f04840c) into main (e7d2276) will increase coverage by 0.01%.
The diff coverage is 33.33%.

@@             Coverage Diff              @@
##               main    #6288      +/-   ##
============================================
+ Coverage     85.19%   85.20%   +0.01%     
+ Complexity     4029     4017      -12     
============================================
  Files           568      567       -1     
  Lines         13421    13390      -31     
  Branches       2376     2371       -5     
============================================
- Hits          11434    11409      -25     
+ Misses          829      825       -4     
+ Partials       1158     1156       -2     

Impacted Files	Coverage Δ
...kotlin/io/gitlab/arturbosch/detekt/api/BaseRule.kt	95.45% <ø> (-4.55%)	⬇️
...otlin/io/gitlab/arturbosch/detekt/core/Analyzer.kt	86.27% <ø> (+0.83%)	⬆️
...b/arturbosch/detekt/core/suppressors/Suppressor.kt	66.66% <ø> (-4.77%)	⬇️
...n/io/github/detekt/report/sarif/RuleDescriptors.kt	36.84% <0.00%> (+6.40%)	⬆️
...io/gitlab/arturbosch/detekt/core/rules/RuleSets.kt	96.15% <100.00%> (+6.49%)	⬆️

... and 1 file with indirect coverage changes

[3flex]

Closes #5192 I assume?

[cortinico]

Closes #5192 I assume?

Yup added 👍