Remove `ancestor_inherited` to `ancestor_inherited` transitions

What does this MR do and why?

Remove ancestor_inherited to ancestor_inherited namespace state transitions.

• These were added temporarily to avoid transition errors during the backfill migration.
• The backfill has been finalized https://gitlab.com/gitlab-org/gitlab/blob/4d050da798a4be59978b220aca88376b5e777239/db/post_migrate/20260126124047_finalize_hk_backfill_namespace_state.rb#L1-L21

References

Related to #582768 (closed)

Screenshots or screen recordings

Before	After

How to set up and validate locally

1. Toggle the remove_group_ancestor_inherited_transitions and remove_project_ancestor_inherited_transitions feature flags
2. In the rails console, run Group.where(state: 0).first.unarchive!
   • Depending on the feature flag, this should either raise an error or proceed successfully.

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