In order to not allow users to remove all persited
translations from any resource. A few exceptions were
added:
* Does not apply to globalizable models without
translatable attributes required
* Make a copy of main model error on current translations to be more realistic
As translatable translations already exists in these specs it has more
sense to me to use select_language intead of adding an already existing
language. Anyway both versions behaves the same and specs pass.
Milestones do not have an author so we can not update that attribute.
Adding this conditional fixes this spec: ./spec/features/admin/budget_investment_milestones_spec.rb[1:1:1:10]
