Feature: `on-fail-only` only for new comments

[tKe]

We wanted to enable on-fail-only to reduce noise in PRs. We currently use overwrite-comment for the same reason.

Unfortunately we've noticed that after a test failure and subsequent posting of a comment on the PR with failures, a successful build does not update or remove the comment indicating failures despite there no longer being any failures.

Would it make more sense to change on-fail-only to apply only to posting a new comment and not for updating/overwriting existing comments?

[Ma11hewThomas]

Thanks @tKe, I think that’s a sensible change.

So with on-fail-only: true:

• if a run fails, create the PR comment as today
• if a run passes and no tagged comment exists, do nothing
• if a run passes, or fails, and if a tagged comment already exists, allow update-comment or overwrite-comment

I'll put something together for the next release