The condition `f.include?('rubocop-todo.yml')` will be true also when the new name is used. So add a spec example demonstrating that we don't get a warning for `inherit_from: .rubocop-todo.yml`.

And another thing. If there is an `inherit_from: rubocop-todo.yml` and the user runs `rubocop --auto-gen-config` creating `.rubocop-todo.yml` then I think we should stop execution. There's a risk that the user doesn't see the warning because it will be followed by all the offense reports. We should at least not load the old `rubocop-todo.yml` during generation of `.rubocop-todo.yml`.