Merge pull request #52281 from nikhita/crd-validation-conversion-fix

Automatic merge from submit-queue (batch tested with PRs 51869, 52281). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>..

apiextensions: fix conversion of CRD schema

- [x] Fix conversion of CRD schema to go-openapi types.
- [x] Add roundtrip tests for this conversion: kubernetes/kubernetes#52793. Split into another PR since it touches godeps.

**Release note**:

```release-note
NONE
```

/cc @sttts

Kubernetes-commit: a5144430914d6a314e74346e79617b346285934c

Author: k8s-publish-robot