fix(deps): update dependency checkstyle to v10.20.0

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
checkstyle (source)	10.19.0 -> 10.20.0

---

Release Notes

checkstyle/checkstyle (checkstyle)

### [`v10.20.0`](https://redirect.github.com/checkstyle/checkstyle/compare/checkstyle-10.19.0...checkstyle-10.20.0) [Compare Source](https://redirect.github.com/checkstyle/checkstyle/compare/checkstyle-10.19.0...checkstyle-10.20.0)

---

Configuration

📅 Schedule: Branch creation - "after 10pm every weekday,before 5am every weekday,every weekend" (UTC), Automerge - At any time (no schedule defined).

🚦 Automerge: Enabled.

♻ Rebasing: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

• [ ] If you want to rebase/retry this PR, check this box

---

This PR was generated by Mend Renovate. View the repository job log.