Fix current offenses for Gitlab/FeatureFlagKeyDynamic

Fix current offenses for .rubocop_todo/gitlab/feature_flag_key_dynamic.yml

The following discussions from !186357 (merged) should be addressed:

• @dgruzd started a discussion: (+1 comment)

  suggestion (non-blocking): I believe that ee/app/services/search/zoekt/info_service.rb is a valid exception to this rule. We're iterating over all Zoekt feature flags. Should we exclude it right away?

• @reprazent started a discussion:

  I think we should rework this one to not use feature flags at all, it's too easy to get something wrong: https://gitlab.com/gitlab-com/gl-infra/production/-/issues/19532#note_2416195628