fix: skip ingestion when in process callback service return NULL (#533)

Co-authored-by: Yihong Zhou <yihzhou@yihzhou-mn2.linkedin.biz>

Author: yihzhou

dao-api/src/main/java/com/linkedin/metadata/dao/BaseLocalDAO.java

@@ -668,7 +668,7 @@ private <ASPECT extends RecordTemplate> AddResult<ASPECT> aspectUpdateHelper(URN
       AspectUpdateResult result = aspectCallbackHelper(urn, newValue, oldValue, updateTuple.getIngestionParams(), auditStamp);
       newValue = (ASPECT) result.getUpdatedAspect();
       // skip the normal ingestion to the DAO
-      if (result.isSkipProcessing()) {
+      if (newValue == null || result.isSkipProcessing()) {
         return null;
       }
     }