Fixes bug where failed bulk import status was not cleaned up (apache#5176)

The shell and monitor display active bulk imports and this is driven by
custom code in the manager that updates this status as the bulk import
runs.  When a bulk import fate operation failed it was not clearing
this.

Author: keith-turner

server/manager/src/main/java/org/apache/accumulo/manager/tableOps/bulkVer2/PrepBulkImport.java

@@ -323,5 +323,6 @@ public void undo(FateId fateId, Manager environment) throws Exception {
     // unreserve sourceDir/error directories
     Utils.unreserveHdfsDirectory(environment, bulkInfo.sourceDir, fateId);
     Utils.getReadLock(environment, bulkInfo.tableId, fateId).unlock();
+    environment.removeBulkImportStatus(bulkInfo.sourceDir);
   }
 }