Allow setting custom ID property on PremiumCheckbox

Note, this fixes a regression introduced V6 -> V7

src/Nri/Ui/PremiumCheckbox/V8.elm

@@ -1,5 +1,6 @@
 module Nri.Ui.PremiumCheckbox.V8 exposing
     ( view
+    , id
     , selected, partiallySelected
     , premium, showPennant
     , Attribute
@@ -39,6 +40,15 @@ import String exposing (toLower)
 import String.Extra exposing (dasherize)
 
 
+{-| Set a custom ID for this checkbox and label. If you don't set this,
+we'll automatically generate one from the label you pass in, but this can
+cause problems if you have more than one checkbox with the same label on
+the page. Use this to be more specific and avoid issues with duplicate IDs!
+-}
+id : String -> Attribute msg
+id id_ =
+    Attribute (\config -> { config | id = Just id_ })
+
 {-| This disables the input
 -}
 disabled : Attribute msg