chore(deps): update docker.io/alpine docker tag to v3.23 (#28)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| docker.io/alpine | final | minor | `3.22` -> `3.23` |

---

### 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.

---

 - [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check this box

---

This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).
<!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiI0Mi4yNi4xMSIsInVwZGF0ZWRJblZlciI6IjQyLjI2LjExIiwidGFyZ2V0QnJhbmNoIjoibWFpbiIsImxhYmVscyI6W119-->

Reviewed-on: #28
Reviewed-by: t.behrendt <t.behrendt@noreply.localhost>
Co-authored-by: Renovate Bot <renovate@t00n.de>
Co-committed-by: Renovate Bot <renovate@t00n.de>

Dockerfile

@@ -1,4 +1,4 @@
-FROM docker.io/alpine:3.22@sha256:4b7ce07002c69e8f3d704a9c5d6fd3053be500b7f1c69fc0d80990c2ad8dd412 AS base
+FROM docker.io/alpine:3.23@sha256:51183f2cfa6320055da30872f211093f9ff1d3cf06f39a0bdb212314c5dc7375 AS base
 
 # Add edge repository for postgresql18-client
 RUN echo '@edge http://dl-cdn.alpinelinux.org/alpine/edge/main' >> /etc/apk/repositories