Fix scheduled event firing order in backtesting
Fix scheduled event firing order in backtesting

When backtesting with multiple scheduled events, these were fired in unpredictable order, not respecting the expected sequence sorted by time.

QuantConnect/Lean,jameschch/Lean,kaffeebrauer/Lean,redmeros/Lean,JKarathiya/Lean,redmeros/Lean,kaffeebrauer/Lean,StefanoRaggi/Lean,AlexCatarino/Lean,kaffeebrauer/Lean,AnshulYADAV007/Lean,AnshulYADAV007/Lean,JKarathiya/Lean,QuantConnect/Lean,QuantConnect/Lean,jameschch/Lean,Jay-Jay-D/LeanSTP,AlexCatarino/Lean,StefanoRaggi/Lean,Jay-Jay-D/LeanSTP,AnshulYADAV007/Lean,StefanoRaggi/Lean,AnshulYADAV007/Lean,jameschch/Lean,redmeros/Lean,JKarathiya/Lean,AnshulYADAV007/Lean,jameschch/Lean,StefanoRaggi/Lean,QuantConnect/Lean,kaffeebrauer/Lean,jameschch/Lean,AlexCatarino/Lean,JKarathiya/Lean,kaffeebrauer/Lean,Jay-Jay-D/LeanSTP,StefanoRaggi/Lean,Jay-Jay-D/LeanSTP,redmeros/Lean,AlexCatarino/Lean,Jay-Jay-D/LeanSTP