Update AlphaStreamsFeeModel.cs
Update AlphaStreamsFeeModel.cs

Small tidying up of code, no performance fixes

jameschch/Lean,StefanoRaggi/Lean,StefanoRaggi/Lean,AlexCatarino/Lean,QuantConnect/Lean,jameschch/Lean,QuantConnect/Lean,JKarathiya/Lean,jameschch/Lean,StefanoRaggi/Lean,StefanoRaggi/Lean,QuantConnect/Lean,jameschch/Lean,AlexCatarino/Lean,AlexCatarino/Lean,JKarathiya/Lean,jameschch/Lean,JKarathiya/Lean,JKarathiya/Lean,QuantConnect/Lean,AlexCatarino/Lean,StefanoRaggi/Lean