Update gradle/gradle-build-action action to v2.8.1

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
gradle/gradle-build-action	action	patch	v2.8.0 -> v2.8.1

---

Release Notes

gradle/gradle-build-action (gradle/gradle-build-action)

### [`v2.8.1`](https://togithub.com/gradle/gradle-build-action/compare/v2.8.0...v2.8.1) [Compare Source](https://togithub.com/gradle/gradle-build-action/compare/v2.8.0...v2.8.1)

---

Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, 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 has been generated by Mend Renovate. View repository job log here.