Some small fixes post merge

com.unity.perception/Runtime/Randomization/Randomizers/Randomizer.cs

         /// </summary>
         protected virtual void OnScenarioComplete() { }
 
-        protected virtual void OnScenarioStart() { }
-
         /// <summary>
         /// OnIterationStart is called at the start of a new Scenario iteration
         /// </summary>

com.unity.perception/Runtime/Randomization/Scenarios/ScenarioBase.cs

         protected virtual void OnEnable()
         {
             activeScenario = this;
+            currentIteration = (int)genericConstants.startFrame;
         }
 
         /// <summary>

com.unity.perception/Runtime/Randomization/Scenarios/UnitySimulationScenario.cs

             }
             else
                 base.OnConfigurationImport();
-            currentIteration = constants.instanceIndex;
+
+            currentIteration = (int)constants.startFrame;
         }
 
         /// <inheritdoc/>