Build and publish charts for OBS/IBS artifacts in gh-pages

[davidcassany]

This PR sets worflows to publish elemental-operator charts as github pages.

Currently there four different repositories defined in github pages:

• dev (https://rancher.github.io/elemental-operator/dev): includes the charts build from main HEAD commit and they point to the OBS Dev container images. Triggered automatically on tagging and on any push to main.
• staging (https://rancher.github.io/elemental-operator/staging): includes the charts build from a tag and they point to OBS Staging. This is triggered manually from a workflow including the tag to build for as a user input.
• stable (https://rancher.github.io/elemental-operator/stable): includes the charts build from a tag and they point to OBS Stable. This is triggered manually from a workflow including the tag to build for as a user input and setting the release flag as true.
• release (https://rancher.github.io/elemental-operator/release): includes the charts build from a tag and they point to the public IBS releases. This is triggered manually from a workflow including the tag to build for as a user input and setting the release flag as true.

Both stable and release repositories are build an published with the same workflow so they are aligned. That means we should only trigger this workflow once suse.com artifacts are on air, not before. In addition this workflow also creates a GH pre-release including the release charts tarball.

In addition this PR also sets the e2e tests to make use of the container images build in OBS as part of the PR workflow. So this repository no longer pushes and pulls anything from quay.io.

I named the repository pointing to registry.suse.com as release, however if anyone has a better name I'd be happy to change it, probably production or official ?

There are still two follow up issues:

• Moving to pure https helm repositories could break any automated elemental installation in place (e.g. our own CI), as helm has a different workflow if charts are coming from an http repo or from an OCI repo. Since this PR does not remove the OBS charts after merging nothing will break as both would be available. As a follow up we should remove the OBS ones and consider publishing also an OCI repository in github registry to facilitate migration by simply changing a URI on already existing setups.
• I still believe there is a lot to clean from the Makefile and probably other bits and pieces from the former days where everything was build in github actions and released from there. We should remove all legacy and consider options for local builds and deployments.

Fixes #460 and part of #333

[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (f1f3c32) 51.50% compared to head (f1c2891) 51.50%.
Report is 1 commits behind head on main.

Additional details and impacted files

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  Coverage   51.50%   51.50%           
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  Files          41       41           
  Lines        5551     5551           
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  Hits         2859     2859           
  Misses       2443     2443           
  Partials      249      249           

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[fgiudici]

The rework of the release process is quite nice!
LGTM - Looks Great To Me 😆

[fgiudici]

Seems to me TAG is no more used in the Makefile.
To be pedantic we may change this to TAG_OPERATOR?=${CHART_VERSION} and use it for the operator build (right now we use ${CHART_VERSION}).
Ok, maybe we could just drop TAG (even in the near future) 😄

[davidcassany]

Gonna take that into account on a follow up Makefile cleanup, looks like we can clean quite some stuff from this Makefile