Use uid 2000, not 1000, for GKE compatibility

[smcgivern]

On GCP (and hence GKE), user IDs in the range 2000 to 4999 are available for custom users: https://cloud.google.com/container-optimized-os/docs/how-to/create-configure-instance#using_cloud-init_with_the_cloud_config_format

Choose an ID from the [2000, 4999] range to avoid collision with other user accounts.

This lets us use runAsNonRoot / runAsUser in a Kubernetes deployment, and I don't think (I hope?) most people won't care that the user ID changed.

Happy to just do this ourselves if we need to, but I figured it was worth a try upstream 🙂

[CLAassistant]

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[robholland]

My impression is that whichever we use we are outside of some providers acceptable ranges, but I'll do some more research here.

[smcgivern]

Yes, frustratingly I can't actually find a good list - even GCP doesn't have this documented particularly well.

[robholland]

I'm going to mark this wontfix for now, I don't think there is a safe range that works on all providers.