Removed 10.6 build issues from TODO now that that's done.
Removed 10.6 build issues from TODO now that that's done.

UIKit0/ui,janstk/ui,beni55/ui,ProtonMail/ui,292388900/ui,hajimehoshi/ui,292388900/ui,hajimehoshi/ui,HunterChen/ui,robbiev/ui,beni55/ui,HunterChen/ui,UIKit0/ui,janstk/ui,ProtonMail/ui,cainiaocome/ui,UIKit0/ui,mirrr/ui,HunterChen/ui,robbiev/ui,janstk/ui,cainiaocome/ui,hajimehoshi/ui,beni55/ui,cainiaocome/ui,robbiev/ui,mirrr/ui,292388900/ui,mirrr/ui,ProtonMail/ui