Using github token as part helm install action

[assaf-grth]

Hi,
Would it be possible not to require github token for this action?
We shouldn't create or have an empty reference in our pipelines when not required...

Hi,
Just bumped into that warning

Why is a GITHUB_TOKEN variable required in such step?

Getting helm version is a standard web request that doesn't require any special authentication + I don't require this variable and don't want to add an empty var just to avoid the warning..

Originally posted by @assaf-grth in #96