Draft: Resolve "Kube: create sidecar container to clean uploaded file"

Closes #18 (closed)

backend/Dockerfile

@@ -16,7 +16,7 @@ FROM python:3.11.4-slim-bookworm as django
 
 RUN apt update -y && apt upgrade -y && apt install -y python3-dev libpq-dev cron
 
-RUN useradd -ms /bin/bash worker && usermod -aG cron worker
+RUN useradd -ms /bin/bash worker && usermod -aG crontab worker
 
 WORKDIR  /code