Allow to pull a chart from any branch

[varditn]

Expected Behaviour

When setting non-packaged charts in prereqCharts, additionalValuesor dependencies. You could specify a git repo with specific branch or tag name and Armador will pull the chart from that specific change.

Actual Behaviour

Armador pulls charts only from master branch.

Example:

prereqCharts:
  - cert-manager:
      packaged: false
      repo: https://github.com/jetstack/cert-manager.git:[branch_name]
      pathToChart: helm/cert-manager
      overrideValueFiles:
        - values.yaml