Backend test coverage report

[seluianova]

Short description

I suggest applying the kover plugin to be able to build test coverage reports in the backend. It allows you to see the test coverage per line of code like this:

Side effects

This creates a bit of clutter in the circle ci artifacts. Alternatives to the clutter would be:

• attach all files as an archive, but it would require an additional download/unzip action to view the report
• connect additional tools to upload and view reports there (for example, CMS uses Code Climate: https://codeclimate.com/github/digitalfabrik/integreat-cms/code)
• do not generate a report in ci, use only locally

Testing

• build the report locally: ./gradlew koverHtmlReport or
• view in circleci:

Resolved issues

n/a

Additional info

Our current test coverage is 31.4741% (per line)