chore(deps): bump github.com/open-policy-agent/cert-controller (#780)

Bumps [github.com/open-policy-agent/cert-controller](https://github.com/open-policy-agent/cert-controller) from 0.15.0 to 0.16.0.
- [Release notes](https://github.com/open-policy-agent/cert-controller/releases)
- [Commits](https://github.com/open-policy-agent/cert-controller/compare/v0.15.0...v0.16.0)

---
updated-dependencies:
- dependency-name: github.com/open-policy-agent/cert-controller
  dependency-version: 0.16.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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