Prevent duplicate subscriptions in live feed
Prevent duplicate subscriptions in live feed

This is a mirror change to that which was done in the file system feed.
Basically, if we already have a subscription then we shouldn't
be adding it again

kaffeebrauer/Lean,Phoenix1271/Lean,redmeros/Lean,andrewhart098/Lean,redmeros/Lean,Jay-Jay-D/LeanSTP,Jay-Jay-D/LeanSTP,QuantConnect/Lean,AnObfuscator/Lean,young-zhang/Lean,QuantConnect/Lean,Mendelone/forex_trading,jameschch/Lean,squideyes/Lean,Mendelone/forex_trading,devalkeralia/Lean,JKarathiya/Lean,JKarathiya/Lean,jameschch/Lean,kaffeebrauer/Lean,AnshulYADAV007/Lean,Phoenix1271/Lean,kaffeebrauer/Lean,StefanoRaggi/Lean,StefanoRaggi/Lean,redmeros/Lean,QuantConnect/Lean,AnshulYADAV007/Lean,andrewhart098/Lean,AlexCatarino/Lean,AnObfuscator/Lean,Mendelone/forex_trading,young-zhang/Lean,AlexCatarino/Lean,squideyes/Lean,andrewhart098/Lean,AlexCatarino/Lean,StefanoRaggi/Lean,kaffeebrauer/Lean,jameschch/Lean,devalkeralia/Lean,devalkeralia/Lean,tomhunter-gh/Lean,Mendelone/forex_trading,AnshulYADAV007/Lean,kaffeebrauer/Lean,QuantConnect/Lean,AlexCatarino/Lean,jameschch/Lean,jameschch/Lean,AnshulYADAV007/Lean,young-zhang/Lean,tomhunter-gh/Lean,JKarathiya/Lean,tomhunter-gh/Lean,squideyes/Lean,StefanoRaggi/Lean,tomhunter-gh/Lean,devalkeralia/Lean,andrewhart098/Lean,StefanoRaggi/Lean,JKarathiya/Lean,redmeros/Lean,young-zhang/Lean,AnshulYADAV007/Lean,Phoenix1271/Lean,Jay-Jay-D/LeanSTP,squideyes/Lean,Jay-Jay-D/LeanSTP,AnObfuscator/Lean,AnObfuscator/Lean,Phoenix1271/Lean,Jay-Jay-D/LeanSTP