The difference between Surefire and iDFlakies/testrunner is because they run tests from a different current directory: mvn -pl innodb-java-reader-cli test runs from innodb-java-reader/innodb-java-reader-cli whereas mvn -pl innodb-java-reader-cli testrunner:testplugin runs from just innodb-java-reader. If you replace mvn -pl innodb-java-reader-cli testrunner:testplugin with cd innodb-java-reader-cli; mvn testrunner:testplugin, it works as expected.
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