[KMP] Fix resolution of Android test classpaths

[cortinico]

This PR depends on #4025

The approach used inside the KMP support for detekt-gradle-plugin was not working correctly for tests sourcesets of Android targets. I fixed it by delegating the creation of detekt tasks for android() targets to DetektAndroid. This will also make sure that the behavior between a pure Android project and a KMP project with an Android target is closer.

Fixes #3840

[codecov]

Codecov Report

Merging #4026 (9d0ce43) into main (66049c5) will not change coverage.
The diff coverage is n/a.

❗ Current head 9d0ce43 differs from pull request most recent head 25d3edd. Consider uploading reports for the commit 25d3edd to get more accurate results

@@            Coverage Diff            @@
##               main    #4026   +/-   ##
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  Coverage     83.56%   83.56%           
  Complexity     3182     3182           
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  Files           459      459           
  Lines          9092     9092           
  Branches       1771     1771           
=========================================
  Hits           7598     7598           
  Misses          561      561           
  Partials        933      933           

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[picklebento]

Did we test with AGP 4.2 so far? (Not a blocking question but something I am interested in)

[cortinico]

Did we test with AGP 4.2 so far? (Not a blocking question but something I am interested in)

We're already on AGP 4.2.0 👍

[picklebento]

There is a UnnecessaryLet finding in the PR.