snap: Failed publishes of all builds

@nodejs/build I might need some help investigating this I think, there’s not enough of me to spend the time needed on this but Snap users are missing the latest releases.

All releases today were rejected by Snapcraft:

  found errors in file output: unusual mode 'rwxr-sr-x' for entry './bin', unusual mode 'rwxr-sr-x' for entry './lib'

Even master (“nodeedge”) started failing today with the same problem, but it hasn’t before.

I don’t know if this is something new we’ve introduced across all branches, whether it’s something new Launchpad is doing with the builds, or some new checking that Snapcraft has introduced.

The s is pretty weird; why is setgid on for these? Not unreasonable to have these rejected.