Avoid unwanted deployment on prod clusters and inconsistent configuration

[mborne]

Motivation

• Running k8s-install.sh with unwanted kubectl config could lead to problems
• DEVBOX_HOSTNAME, DEVBOX_INGRESS,... should be provided just one time

Actions

DRAFT (have to try with kind and K3S clusters and experiment a declarative approach with ArgoCD)

•  Add a bin/k8s-check-config.sh script ensuring that a label devbox-allowed: true is defined on a namespace

"default" or dedicated "devbox" one?

• Invoke this script in k8s-install.sh scripts

•  Add a bin/k8s-enable-devbox.sh (or something like bin/k8s-configure-devbox.sh)