[to dev/1.3] Fix incorrect overlap unpack when endTime equals sentinel value #16993

Author: shuwenwei

iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/execution/operator/source/SeriesScanUtil.java

@@ -1256,7 +1256,7 @@ private void tryToUnpackAllOverlappedFilesToTimeSeriesMetadata() throws IOExcept
     /*
      * find end time of the first TimeSeriesMetadata
      */
-    long endTime = -1L;
+    Long endTime = null;
     if (!seqTimeSeriesMetadata.isEmpty() && unSeqTimeSeriesMetadata.isEmpty()) {
       // only has seq
       endTime = orderUtils.getOverlapCheckTime(seqTimeSeriesMetadata.get(0).getStatistics());
@@ -1274,7 +1274,7 @@ private void tryToUnpackAllOverlappedFilesToTimeSeriesMetadata() throws IOExcept
     /*
      * unpack all directly overlapped seq/unseq files with first TimeSeriesMetadata
      */
-    if (endTime != -1) {
+    if (endTime != null) {
       unpackAllOverlappedTsFilesToTimeSeriesMetadata(endTime);
     }