Action fails when GITHUB_REF does not exist

[billputer]

Certain workflows don't set a GITHUB_REF variable, because the triggering event doesn't have a branch or tag. See GitHub's docs on GITHUB_REF.

However, this action fails with an error when the GITHUB_REF environment variable doesn't exist, with the output ##[error]Missing required environment value. Are you running in GitHub Actions?.

[bennettl]

This is breaking all our pipelines, even if we set role-skip-session-tagging: true its checking for the github env vars which are not set. Not just GITHUB_REF, environment variable

[allisaurus]

Thanks for reporting @sergirosell & @bennettl - sounds like the issue with the runner was rolled back, but we're working on fixing this for GITHUB_REF and the other env vars when tagging is skipped.

[allisaurus]

FYI we are tracking issues with remaining env vars here: #105