Run on draft PRs and don't fail fast

[SystemKeeper]

• I think we should also run on draft PRs. It does not make sense to manually move to "Ready-for-review" and then back to Draft just for the workflows to run (also this does not work without another push right now, because the type "ready_to_review" is not checked by default, see https://github.com/orgs/community/discussions/25722#discussioncomment-3248917)
• "fail-fast" should be disabled. We currently run 4 test scenarios (23, 27, 28, main), when one of these scenarios fail, all others are cancelled as well. When there's a specific issue in only one of the scenarios, the others should still continue to run.