chore(deps): update docker.io/library/alpine docker tag to v3.23.4 (#57)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [docker.io/library/alpine](https://hub.docker.com/_/alpine) ([source](https://github.com/alpinelinux/docker-alpine)) | final | patch | `3.23.3` → `3.23.4` |

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Reviewed-on: #57
Reviewed-by: t.behrendt <2+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/library/alpine:3.23.3@sha256:25109184c71bdad752c8312a8623239686a9a2071e8825f20acb8f2198c3f659 AS base
+FROM docker.io/library/alpine:3.23.4@sha256:5b10f432ef3da1b8d4c7eb6c487f2f5a8f096bc91145e68878dd4a5019afde11 AS base
 
 # Add edge repository for postgresql18-client
 RUN echo '@edge http://dl-cdn.alpinelinux.org/alpine/edge/main' >> /etc/apk/repositories