:seedling: Bump github.com/cert-manager/cert-manager (#2678)

Bumps [github.com/cert-manager/cert-manager](https://github.com/cert-manager/cert-manager) from 1.20.1 to 1.20.2.
- [Release notes](https://github.com/cert-manager/cert-manager/releases)
- [Changelog](https://github.com/cert-manager/cert-manager/blob/master/RELEASE.md)
- [Commits](https://github.com/cert-manager/cert-manager/compare/v1.20.1...v1.20.2)

---
updated-dependencies:
- dependency-name: github.com/cert-manager/cert-manager
  dependency-version: 1.20.2
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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