ObjectReleaseTracker completely useless in all SolrTestCaseJ4 based tests - masking unclosed InputStream in some SolrStream usecases

SolrTestCase has a @ClassRule named solrClassRules which calls ObjectReleaseTracker.clearObjectTrackerAndCheckEmpty() in it's afterIfSuccessful() method to ensure that any objects which use ObjectReleaseTracker are correctly released (ie: closed)

...BUT...

SolrTestCaseJ4 has an @AfterClass method named teardownTestCases() which calls ObjectReleaseTracker.clear() before the afterIfSuccessful() method of it's parent class's solrClassRules gets to run.

... Which means that ObjectReleaseTracker is completley useless in every test that descends from SolrTestCaseJ4.