This ensures that project authorizations are refreshed when moving a
project from one namespace to another. When doing so the permissions for
all users of both the old and new namespaces are refreshed.

See #26194 for more information.

Fix missing group members from Import/Export

Closes #25124

See merge request !8923

There is now a `Projects::Settings` module, for the members
controller. Ensure that we get the actual settings, not that module.

Due to autoloading and Ruby scoping, the .update file was never being
updated due to this error:

```
NoMethodError: undefined method `pages' for Projects::Settings:Module
        from /opt/gitlab/embedded/service/gitlab-rails/app/services/projects/update_pages_configuration_service.rb:50:in `pages_update_file'
        from /opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/metrics/instrumentation.rb:157:in `pages_update_file'
        from (irb):6
        from /opt/gitlab/embedded/lib/ruby/gems/2.3.0/gems/railties-4.2.7.1/lib/rails/commands/console.rb:110:in `start'
        from /opt/gitlab/embedded/lib/ruby/gems/2.3.0/gems/railties-4.2.7.1/lib/rails/commands/console.rb:9:in `start'
        from /opt/gitlab/embedded/lib/ruby/gems/2.3.0/gems/railties-4.2.7.1/lib/rails/commands/commands_tasks.rb:68:in `console'
        from /opt/gitlab/embedded/lib/ruby/gems/2.3.0/gems/railties-4.2.7.1/lib/rails/commands/commands_tasks.rb:39:in `run_command!'
        from /opt/gitlab/embedded/lib/ruby/gems/2.3.0/gems/railties-4.2.7.1/lib/rails/commands.rb:17:in `<top (required)>'
        from bin/rails:9:in `require'
```

This error was caught and discarded quietly. This fix exercises this code and fixes the scope problem.

Closes gitlab-com/infrastructure#1058