**What version of TellMeWhen are you using? **

8.6.8 Classic

What steps will reproduce the problem?

1. Create icon with check cast bar for interrupt able

Additional Info

`
Interface\AddOns\TellMeWhen\Components\Core\Icon.lua:240: Attempt to register unknown event "UNIT_SPELLCAST_NOT_INTERRUPTIBLE"
Interface\AddOns\TellMeWhen\Components\Core\Icon.lua:240: Attempt to register unknown event "UNIT_SPELLCAST_NOT_INTERRUPTIBLE"
Interface\AddOns\TellMeWhen\TellMeWhen.lua:2781: in function <Interface\AddOns\TellMeWhen\TellMeWhen.lua:2738>

Interface\AddOns\TellMeWhen\Components\Core\Icon.lua:251: Attempt to unregister unknown event "UNIT_SPELLCAST_NOT_INTERRUPTIBLE"
[C]: in function UnregisterEvent' Interface\AddOns\TellMeWhen\Components\Core\Icon.lua:251: in function UnregisterAllEvents'
Interface\AddOns\TellMeWhen\Components\Core\Icon.lua:863: in function DisableIcon' Interface\AddOns\TellMeWhen\Components\Core\Icon.lua:957: in function <Interface\AddOns\TellMeWhen\Components\Core\Icon.lua:907> (tail call): ? [C]: ? [string "safecall Dispatcher[1]"]:9: in function <[string "safecall Dispatcher[1]"]:5> (tail call): ? ...nterface\AddOns\TellMeWhen\Components\Core\Group.lua:497: in function <...nterface\AddOns\TellMeWhen\Components\Core\Group.lua:425> (tail call): ? [C]: ? [string "safecall Dispatcher[1]"]:9: in function <[string "safecall Dispatcher[1]"]:5> (tail call): ?