### Check existing issues - [x] I've verified that this request isn't described by any existing issues. ### Request The `snapcraft upload` CLI tool should return a different return value when it ends with “need manual review” status, compared to actual errors. ### The problem it solves A problem we encountered on GIMP's release pipeline is that this "need manual review" status broke our pipeline (as it apparently didn’t return 0). As a consequence: 1. it stopped after uploading one out of the 2 archs; 2. a few other steps in the release procedure were made more annoying (because for failed pipelines, Gitlab won’t generate some “easy” redirection URLs used by our scripts to publish other binaries to our download infra). We still want to see real failures, but “need manual review” is not actually a failure, right? We just wait a bit to get the manual validation. So I’d like for our pipeline to still pass as success in this “manual review” case, which is why I wish to be able to react conditionally on the return value. P.S.: as initially [reported on the snapcraft forums](https://forum.snapcraft.io/t/personal-files-request-for-gimp/50315/10?u=gimp).