fix: deduplicate OpenAPI definitions for GVKParser (#587) (2.9)

[crenshaw-dev]

• fix: deduplicate OpenAPI definitions for GVKParser

• do the thing that was the whole point

• more logs

• don't uniquify models

• schema for both

• more logs

• fix logic

• better tainted gvk handling, better docs, update mocks

• add a test

• improvements from comments

---