model.dup should copy model values with nil public_uid

[equivalent]

curent imlplementation:

work = Work.last
work.public_uid == 'asdfghjkl'

work_dup = model.dup
work_dup.public_uid == 'asdfghjkl' #this is wrong !!!

this should be:

work = Work.last
work.public_uid == 'asdfghjkl'

work_dup = model.dup
work_dup.public_uid == nil # this is correct !

Why?

read more: https://blog.appsignal.com/2019/02/26/diving-into-dup-and-clone.html

important part:

#dup to allow you to duplicate a record without its "internal" state (id and timestamps),

Rails implement it same way

https://github.com/rails/rails/blob/85f45350e6d3fb6284c744d36b77b79ce639dfee/activerecord/lib/active_record/timestamp.rb#L50