Refactor: rollback default round value to null CalculateDeltaNode

rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/metadata/CalculateDeltaNodeConfiguration.java

@@ -40,7 +40,6 @@ public class CalculateDeltaNodeConfiguration implements NodeConfiguration<Calcul
         configuration.setAddPeriodBetweenMsgs(false);
         configuration.setPeriodValueKey("periodInMs");
         configuration.setTellFailureIfDeltaIsNegative(true);
-        configuration.setRound(0);
         return configuration;
     }
 

rule-engine/rule-engine-components/src/test/java/org/thingsboard/rule/engine/metadata/CalculateDeltaNodeTest.java

@@ -110,7 +110,6 @@ public class CalculateDeltaNodeTest {
         assertFalse(config.isAddPeriodBetweenMsgs());
         assertEquals(config.getPeriodValueKey(), "periodInMs");
         assertTrue(config.isTellFailureIfDeltaIsNegative());
-        assertEquals(config.getRound(), 0);
     }
 
     @Test