Fix flaky integration test on namespace cleanup

[csviri]

Currently the integration test sometimes failing, it seems that the problem is with the namespace cleanup:
https://github.com/java-operator-sdk/java-operator-sdk/runs/4296723886?check_suite_focus=true

[csviri]

It seems that it takes time to clean the pod of the deployment, this is why the test timeouts. Interesting is that only if I run all the tests not just the single test.