Kubernetes CLI commands are still implemented in Core

[potiuk]

Body

The CLI commands provided by cncf.kubernetes provider are still implemented in airlfow.cli.kubernetes. While we cannot fully remove them from Airflow for back-compatibility with old provider versions, we should move them to k8S similarly as we did for celery (leaving the old implementation in core for old providers).

Committer

• I acknowledge that I am a maintainer/committer of the Apache Airflow project.