Restore code coverage via kover-maven-plugin - #4401

Current aggregated coverage:

[INFO] --- kover:0.9.9:log (default) @ assertj-core-tests ---
[INFO] application line coverage: 92.9863%

[INFO] --- kover:0.9.9:log (default) @ assertj-guava-tests ---
[INFO] application line coverage: 93.8127%

I'll look into integrating the XML reports with GitHub Code Coverage (see an example here of what the coverage report looks like).

By setting this up, I realize now that assertj-core-tests and assertj-guava-tests can act as aggregate modules with the jacoco:report-aggregate goal. What is still unclear to me is whether this is still required:

write your own check logic on the xml report (total coverage is reported at the root)

I'll set up an equivalent JaCoCo configuration and compare the result.

Looks good. No mutations were possible for these changes.
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🏷️ Commit: c7a2018
▶️ Tests: 92188 executed
⚪️ Checks: 21/21 completed

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