Update Interface.lua

[paigedwight]

Fix for the following error after today's patch

1x Immersion\Interface.lua:26: 'for' step must be a number
[string "@Immersion\Interface.lua"]:26: in function <Immersion\Interface.lua:24>
[string "=(tail call)"]: ?
[string "@Immersion\Mixins\Titles.lua"]:184: in function `?'
[string "@Immersion\Mixins\Titles.lua"]:106: in function <Immersion\Mixins\Titles.lua:104>

Locals:
lambda = <function> defined @Immersion\Interface.lua:32
step = nil
data = <table> {
}
(for index) = 1
(for limit) = 0
(for step) = nil
(*temporary) = 0
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = nil
(*temporary) = "'for' step must be a number"