- Add debian image based on `stable-slim`, desire for this is largely
around my use case using Azure DevOps which makes it challenging to
use images which are not glibc based.
- Drop support for helm2 in the docker images. This is a tricky one but
given that I was having errors during the docker build for helm2 and
the fact that it has been EoL for a long time now made me think that
this was the correct move.
- As a "while I'm in here" I've upgraded kubectl and helm. I've popped
on the most current patch of the last release (v1.20.3) to give a
slightly broader support for different Kubernetes versions.
- Reworked CI to support pushing a debian and alpine base, and dropped
support for the helm2 versions.