fix MoveReplicaHdfsFailoverTest after SOLR-16962 (#2525)

the changes made by SOLR-16962 to ZkController and MoveReplicaCmd
resolve the conflation of ulog and tlog dir, and remove some
related hacky compensations for this conflation. The nightly test
MoveReplicaHdfsFailoverTest was still compensating for this issue
when it no longer needs to, and was thus failing.

(cherry picked from commit 4a12f8a)

solr/modules/hdfs/src/test/org/apache/solr/hdfs/cloud/MoveReplicaHdfsFailoverTest.java

@@ -91,7 +91,6 @@ public void testDataDirAndUlogAreMaintained() throws Exception {
             .setNode(cluster.getJettySolrRunner(0).getNodeName())
             .process(cluster.getSolrClient());
 
-    ulogDir += "/tlog";
     ZkStateReader zkStateReader = cluster.getZkStateReader();
     assertTrue(ClusterStateUtil.waitForAllActiveAndLiveReplicas(zkStateReader, 120000));