fixed NPE in subscription service

application/src/main/java/org/thingsboard/server/service/subscription/DefaultTbLocalSubscriptionService.java

@@ -334,7 +334,7 @@ public class DefaultTbLocalSubscriptionService implements TbLocalSubscriptionSer
     }
 
     private void onTimeSeriesUpdate(UUID entityId, List<TsKvEntry> data, TbCallback callback) {
-        entityUpdates.get(entityId).timeSeriesUpdateTs = System.currentTimeMillis();
+        getEntityUpdatesInfo(entityId).timeSeriesUpdateTs = System.currentTimeMillis();
         processSubscriptionData(entityId,
                 sub -> TbSubscriptionType.TIMESERIES.equals(sub.getType()),
                 s -> {
@@ -371,7 +371,7 @@ public class DefaultTbLocalSubscriptionService implements TbLocalSubscriptionSer
     }
 
     private void onAttributesUpdate(UUID entityId, String scope, List<TsKvEntry> data, TbCallback callback) {
-        entityUpdates.get(entityId).attributesUpdateTs = System.currentTimeMillis();
+        getEntityUpdatesInfo(entityId).attributesUpdateTs = System.currentTimeMillis();
         processSubscriptionData(entityId,
                 sub -> TbSubscriptionType.ATTRIBUTES.equals(sub.getType()),
                 s -> {
@@ -639,4 +639,8 @@ public class DefaultTbLocalSubscriptionService implements TbLocalSubscriptionSer
         throw new TbRateLimitsException(message);
     }
 
+    private TbEntityUpdatesInfo getEntityUpdatesInfo(UUID entityId) {
+        return entityUpdates.computeIfAbsent(entityId, id -> new TbEntityUpdatesInfo(0));
+    }
+
 }