Delegate locale resolution to LocaleResolver
Delegate locale resolution to LocaleResolver

https://github.com/ManageIQ/manageiq/pull/13582 extracted this logic in
the main repo so it could be reused without inheriting all of
`ApplicationController`. This PR updates `ApplicationController` to
delegate to the newly extracted service.

ManageIQ/manageiq-ui-classic,ManageIQ/manageiq-ui-classic,ManageIQ/manageiq-ui-classic,ManageIQ/manageiq-ui-classic