chore(deps): update docker.io/library/python docker tag to v3.12.4

This MR contains the following updates:

Package	Type	Update	Change
docker.io/library/python	final	patch	3.12.3-slim -> 3.12.4-slim

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Dockerfile

-FROM docker.io/library/python:3.12.3-slim
+FROM docker.io/library/python:3.12.4-slim
 
 ARG BUILD_DEPS="build-essential librsync-dev gcc gettext"
 ARG RUN_DEPS="librsync2 gnupg"