fix(search-account): copy index scope

[loicsay]

Q	A
Bug fix?	yes
New feature?	no
BC breaks?	no
Related Issue	-
Need Doc update	no

Describe your change

• Related to [DEX-255] feat: algolia app migrate cli#77

Taking scope into account to copy rules, synonyms and settings only when there's no scope. If one (or multiple) scope options are passed, copy the index depending on the parameters.

What problem is this fixing?

scope option passed to search.NewAccount().CopyIndex(...) is ignored.

[samouss]

It looks like he scope option only exists for the search_client.copy_index function, but not for the account_client.copy_index. We may want to stick to the API client specs and avoid implementing a new option not present in other languages. I think @VladislavFitz may have an better view than me on this!