Prewarm setup

Assets/Samples/UnityLogo/UnityLogo.vfx

       lightProbeUsage: 0
     m_CullingFlags: 3
     m_UpdateMode: 1
-    m_PreWarmDeltaTime: 0.05
-    m_PreWarmStepCount: 0
+    m_PreWarmDeltaTime: 0.14285715
+    m_PreWarmStepCount: 35
     m_InitialEventName: OnPlay
   m_Systems:
   - type: 0

Assets/Samples/Volumetric/Volumetric.vfx

       lightProbeUsage: 0
     m_CullingFlags: 3
     m_UpdateMode: 1
-    m_PreWarmDeltaTime: 0.05
-    m_PreWarmStepCount: 0
+    m_PreWarmDeltaTime: 0.14285715
+    m_PreWarmStepCount: 70
     m_InitialEventName: OnPlay
   m_Systems:
   - type: 0