[feature] draft releases support for uploading provenance

[developer-guy]

Is your feature request related to a problem? Please describe.
This might be related to a problem but at the same time, this is a feature.

Describe the solution you'd like
While working on the osv-scanner project, I realized that they mark their release as a draft for some reason. In that case, if we set the upload-assets parameter of the Generic SLSA 3 Generator as true, we see two different releases with the same tag, one is marked as draft the other is marked as latest. Then I dag into the problem a bit, and noticed that the Generic SLSA 3 Generator uses soft-props/action-gh-release to upload the provenance file, here and here. There is a draft option available in the parameters of the action-gh-release GitHub Action.

So, maybe we can add a new parameter to these generators for people who might want to mark their release as a draft, if so, they can pass that parameter to the action-gh-release to avoid having duplicate releases.

PTAL @laurentsimon

[ianlewis]

I think this is the same as #1476? Could you maybe comment on #1476 about osv-scanner?

I'll go ahead and close this and defer to that issue but feel free to re-open if you think there is more that should be covered in a separate issue.