Nice Kata! However, Java tests (random tests) dont really test the solution properly, as there are 99,9% chance that the time chunk will end with seconds. This way, u can just use "...and second(s)", as there are almost never a test ending with days/hours (which needs to be solved through "...days and 3 hours").
I suggest adding some manually writen tests exactly for those cases, otherwise not fully-solved Katas are getting through.