POI：fix BasteTestCellComment#attemptToSave2CommentsWithSameCoordinates to work with different behaviors of HSSFWorkbook and XSSFWorkbook
POI：fix BasteTestCellComment#attemptToSave2CommentsWithSameCoordinates to work with different behaviors of HSSFWorkbook and XSSFWorkbook

antony-liu/npoi,tonyqus/npoi