chore(deps): update docker (minor)

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
docker.io/library/alpine	final	minor	3.19.1 -> 3.21.0
docker.io/library/golang	stage	minor	1.22.0 -> 1.23.4
docker/build-push-action	action	pinDigest	-> ca052bb
docker/login-action	action	pinDigest	-> 9780b0c
docker/setup-buildx-action	action	pinDigest	-> 6524bf6

---

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.

👻 Immortal: This PR will be recreated if closed unmerged. Get config help if that's undesired.

---

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

---

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