Update dependency docker.io/library/alpine to v3.15.4

This MR contains the following updates:

Package	Type	Update	Change
docker.io/library/alpine	final	patch	3.15.3 -> 3.15.4

---

Configuration

📅 Schedule: At any time (no schedule defined).

🚦 Automerge: Disabled due to failing status checks.

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

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

---

This MR has been generated by Renovate Bot. The local configuration can be found in the local Renovate Bot repository.