chore(docker): bump python in /Docker/prod/GUI

Bumps python from 3.11-slim to 3.12-slim.

---
updated-dependencies:
- dependency-name: python
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Docker/prod/GUI/Dockerfile

@@ -1,4 +1,4 @@
-FROM --platform=linux/amd64 python:3.11-slim as runner
+FROM --platform=linux/amd64 python:3.12-slim as runner
 
 LABEL org.opencontainers.image.title="Drifty GUI"
 LABEL org.opencontainers.image.description="Drifty is an Open-Source Interactive File Downloader System built with Java"