Enable Kotlin test fixtures support

[0xnm]

What does this PR do?

Read more here https://developer.android.com/build/releases/gradle-plugin#kotlin_support_for_test_fixtures_in_android_gradle_plugin.

Review checklist (to be filled by reviewers)

• Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• Make sure you discussed the feature or bugfix with the maintaining team in an Issue
• Make sure each commit and the PR mention the Issue number (cf the CONTRIBUTING doc)

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 70.02%. Comparing base (87cc448) to head (dc4bcfe).
Report is 11 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #2234      +/-   ##
===========================================
- Coverage    70.02%   70.02%   -0.00%     
===========================================
  Files          727      727              
  Lines        27036    27053      +17     
  Branches      4556     4558       +2     
===========================================
+ Hits         18931    18942      +11     
+ Misses        6828     6827       -1     
- Partials      1277     1284       +7     

see 40 files with indirect coverage changes