Support ability to use a helm values files from a URL

[AndreiPustovalov]

Helm support the ability to use URL as path to values file, e.g.: helm template . -f https://example.com/values.yaml.
It doesn't work with gradle helm plugin as it assume values file is a local file.

It also breaks compatibility with some plugins, for example helm-secrets plugin as it uses "secrets://" prefix before path to values file to decrypt it:

helm upgrade name . -f secrets://secrets.yaml

[JamieSlome]

@AndreiPustovalov - thank you for opening the issue. We welcome any ideas with how to address this or even a PR to kick things off.

[magner669]

There seems to be some support for values from files, albeit in context.of lint rather than rendering: https://unbroken-dome.github.io/projects/gradle-helm-plugin/latest/userguide/index.html#_passing_values_to_the_linter

Do files work with rendering?
Is a URL accepted?