Add more log for testing

Signed-off-by: Tianli Feng <ftianli@amazon.com>

server/src/internalClusterTest/java/org/opensearch/indices/replication/SegmentReplicationIT.java

@@ -915,6 +915,7 @@ public void testScrollCreatedOnReplica() throws Exception {
         final IndexShard replicaShard = getIndexShard(replica, INDEX_NAME);
         final SegmentInfos segmentInfos = replicaShard.getLatestSegmentInfosAndCheckpoint().v1().get();
         final Collection<String> snapshottedSegments = segmentInfos.files(false);
+        logger.info("snapshotted segments: " + snapshottedSegments);
         // opens a scrolled query before a flush is called.
         // this is for testing scroll segment consistency between refresh and flush
         SearchResponse searchResponse = client(replica).prepareSearch()
@@ -960,14 +961,17 @@ public void testScrollCreatedOnReplica() throws Exception {
             scrollHits += searchResponse.getHits().getHits().length;
             searchResponse = client(replica).prepareSearchScroll(searchResponse.getScrollId()).setScroll(TimeValue.timeValueDays(1)).get();
             assertAllSuccessful(searchResponse);
+            logger.info("scrollHits: " + scrollHits + ". scroll id: " + searchResponse.getScrollId());
         } while (searchResponse.getHits().getHits().length > 0);
 
         List<String> currentFiles = List.of(replicaShard.store().directory().listAll());
+        logger.info("currentFiles: " + currentFiles);
         assertTrue("Files should be preserved", currentFiles.containsAll(snapshottedSegments));
 
         client(replica).prepareClearScroll().addScrollId(searchResponse.getScrollId()).get();
 
         currentFiles = List.of(replicaShard.store().directory().listAll());
+        logger.info("currentFiles after clearing scroll: " + currentFiles);
         assertFalse("Files should be cleaned up post scroll clear request", currentFiles.containsAll(snapshottedSegments));
         assertEquals(100, scrollHits);
     }