MINOR: Cleanup log.dirs in ReplicaManagerTest on JVM exit

[gaurav-narula]

ReplicaManagerTest::setupReplicaManagerWithMockedPurgatories creates two log dirs, core/data and core/data2 and test testActiveProducerState creates a partition in core/data2.

This PR adds core/data2 and all files/directories within it to .gitignore.

[gaurav-narula]

CC: @mimaison, please take a look

[mimaison]

Shouldn't we instead update the tests to use temp directories and cleanup any files they create?

[jlprat]

I agree with @mimaison, I think we should make sure the tests clean after themselves. Right now, it seems that data within core/data/ is deleted but the directories are still present.

[gaurav-narula]

Addressed in 4406670

Shouldn't we instead update the tests to use temp directories and cleanup any files they create?

I think the tests deliberately use relative directories because of KAFKA-5759.