Retry on docker registry lookup error

[tmcgilchrist]

Base image builder regularly errors on this transient issue:

failed to solve with frontend dockerfile.v0: failed to solve with frontend gateway.v0: rpc error: code = Unknown desc = ocurrent/opam-staging@sha256:90f036ba79b70d23d08aad99dcaaf9594bc953c9b9a16dd0aa7cee4894939512: failed to do request: Head "https://registry-1.docker.io/v2/ocurrent/opam-staging/manifests/sha256:90f036ba79b70d23d08aad99dcaaf9594bc953c9b9a16dd0aa7cee4894939512": dial tcp: lookup registry-1.docker.io: Temporary failure in name resolution
docker-build failed with exit-code 1
2023-03-02 15:27.29: Job failed: Failed: Build failed

It would be useful to immediately retry on know flakey errors.