fix(choices): readonly record

A Record by itself is not readonly.
Not sure why the eslint rule hasnt noticed that...

Author: EdJoPaTo

source/choices/types.ts

@@ -5,7 +5,7 @@ import {GenericPaginationOptions} from '../buttons/pagination'
 export type Choice = string | number
 export type ChoiceText = string
 export type ChoicesArray = readonly Choice[]
-export type ChoicesRecord = Record<Choice, ChoiceText>
+export type ChoicesRecord = Readonly<Record<Choice, ChoiceText>>
 export type ChoicesMap = ReadonlyMap<Choice, ChoiceText>
 export type Choices = ChoicesArray | ChoicesRecord | ChoicesMap