Provide CI scenario description

What does this MR do and why?

This MR provide a description for each CI scenario, explaining it purpose. This is probably useful for people not familiar with our CI setup.

It also provide a script to extract this information and update the README.md, a link to this part is provided in the MR description template.

Additionally a CI check is performed to ensure this file was updated when needed, and the pre commit hook is updated to run it (similar to what we have for renovate.json)

Fix some markdown minor issues to please the linter

Related reference(s)

Test coverage

CI configuration

Below you can choose test deployment variants to run in this MR's CI.

Click to open to CI configuration

Legend:

Icon	Meaning	Available values
☁️	Infra Provider	capd, capo, capm3
🚀	Bootstrap Provider	kubeadm (alias kadm), rke2
🐧	Node OS	ubuntu, suse
🛠️	Deployment Options	light-deploy, oci, ha, misc
🎬	Pipeline Scenarios	rolling-update, mgmt-rolling-update, k8s-upgrade, sylva-upgrade-from-x.x.x, simple-update, preview, nightly

• 🎬 preview ☁️ capd 🚀 kadm 🐧 ubuntu 🛠️ oci

• 🎬 preview ☁️ capo 🚀 rke2 🐧 suse

• 🎬 preview ☁️ capm3 🚀 rke2 🐧 ubuntu

• ☁️ capd 🚀 kadm 🛠️ light-deploy 🐧 ubuntu

• ☁️ capd 🚀 rke2 🛠️ oci,light-deploy 🐧 suse

• ☁️ capo 🚀 rke2 🛠️ oci 🐧 suse

• ☁️ capo 🚀 kadm 🛠️ oci 🐧 ubuntu

• ☁️ capo 🚀 rke2 🎬 rolling-update 🛠️ ha 🐧 ubuntu

• ☁️ capo 🚀 kadm 🎬 k8s-upgrade 🐧 ubuntu

• ☁️ capo 🚀 rke2 🎬 mgmt-rolling-update 🛠️ ha,misc 🐧 suse

• ☁️ capo 🚀 rke2 🎬 sylva-upgrade-from-1.3.x 🛠️ ha,misc 🐧 ubuntu

• ☁️ capm3 🚀 rke2 🐧 suse

• ☁️ capm3 🚀 kadm 🛠️ oci 🐧 ubuntu

• ☁️ capm3 🚀 kadm 🎬 mgmt-rolling-update 🛠️ ha,misc 🐧 ubuntu

• ☁️ capm3 🚀 rke2 🎬 k8s-upgrade 🛠️ ha 🐧 suse

• ☁️ capm3 🚀 kadm 🎬 rolling-update 🛠️ ha 🐧 ubuntu

• ☁️ capm3 🚀 rke2 🎬 sylva-upgrade-from-1.3.x 🛠️ misc,ha 🐧 suse

• ☁️ capm3 🚀 kadm 🎬 rolling-update 🛠️ ha 🐧 suse

Global config for deployment pipelines

• autorun pipelines
• allow failure on pipelines

Notes:

• Enabling autorun will make deployment pipelines to be run automatically without human interaction
• Disabling allow failure will make deployment pipelines mandatory for pipeline success.
• if both autorun and allow failure are disabled, deployment pipelines will need manual triggering but will be blocking the pipeline

Be aware: after configuration change, pipeline is not triggered automatically. Please run it manually (by clicking the run pipeline button in Pipelines tab) or push new code.