Remove Product Groups at the Stage

Why is this change being made?

We no longer use the word Hive as in this update !91207 (merged) we converted Hive to Product Groups at the Stage Level, this doesn't really work with our existing definition of Product groups - https://about.gitlab.com/company/team/structure/#product-groups and I would recommend streamlining the OKR process to https://about.gitlab.com/handbook/product/product-okrs/#shared-rd-okrs

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