Bumps [k8s.io/api](https://github.com/kubernetes/api) from 0.18.6 to 0.18.8.
- [Release notes](https://github.com/kubernetes/api/releases)
- [Commits](https://github.com/kubernetes/api/compare/v0.18.6...v0.18.8)
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Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>