Build 'helm' with GitHub Actions pipeline

[jadecarino]

Story

As a contributor to the galasa open source project, I want builds to be in the open, and use github actions, so that I can see build logs, see built artifacts, benefit from integration with github actions, and all without using any resources within the secretive IBM firewall.

Background

There are many benefits of moving our infrastructure to use github actions.

• Builds will be immediately kicked off, no 2-minute delay for them to start.
• build logs are available for ages
• built artifacts can be made available within the build results

Objectives:

• Now that we have learned more about GH Actions with the spike story #1719 , we can move on to recreating GH Actions builds for other components that are in the main build chain
• Side by side comparison with Tekton pipeline
• Try out the Docker registry

For reference, look at the existing Tekton pipelines for helm and the associated Tasks that it utilises, but remove/adapt Tasks as appropriate for GitHub actions.

Tasks

• [x] Use GitHub actions to build the 'helm' repository for merges to Main only - create trigger from Helm to build-helm.yaml in automation
• [x] In build-helm.yaml - Use the Helm CLI to uninstall the ecosystem (task uninstall-ecosystem)
• [x] In build-helm.yaml - Use the Helm CLI to reinstall the ecosystem (task install-ecosystem)
• [x] In build-helm.yaml - Use the Helm CLI to test the ecosystem (task test-ecosystem)
• [x] (Jade) set up Kubeconfig secret in GitHub
• [x] (Jade) reactivate trigger when we fully move to GH Actions - disabled for now to avoid duplicate helm installs causing problems (see commented line here)

[jadecarino]

Waiting for 0.36.0 release to merge in PR: https://github.com/galasa-dev/helm/pull/41

[jadecarino]

The workflow is successful but I have got rid of the trigger so the GH and Tekton workflows don't run at the same time and cause issues with ecosystem1. I will reactivate the trigger (and close this item off) when we fully move to GH actions.