docker builds are failing to build linux/arm/v7 images

[willnorris]

Looks to be due to an upstream change in the chainguard go image we are using. Tracking in chainguard-images/images#182

[willnorris]

Not sure how long these logs will still be present, but...

Successful build on Dec 29, 2022: https://github.com/tailscale/golink/actions/runs/3802666560/jobs/6468365100
Failed build today Jan 3, 2023: https://github.com/tailscale/golink/actions/runs/3829017278/jobs/6521295454

Chainguard changed the go image on Dec 30, 2022.