builder: add worker gc policies and labels

[crazy-max]

needs #1430

Adds builder GC Policies with worker labels. Will be displayed when using inspect command:

$ docker buildx inspectName: builder2Driver: docker-containerLast Activity: 2022-11-30 12:42:47 +0100 CETNodes:Name: builder20Endpoint: unix:///var/run/docker.sockDriver Options: env.BUILDKIT_STEP_LOG_MAX_SPEED="10485760" env.JAEGER_TRACE="localhost:6831" image="moby/buildkit:latest" network="host" env.BUILDKIT_STEP_LOG_MAX_SIZE="10485760"Status: runningFlags: --debug --allow-insecure-entitlement security.insecure --allow-insecure-entitlement network.hostBuildKit: v0.10.6Platforms: linux/amd64, linux/amd64/v2, linux/amd64/v3, linux/arm64, linux/riscv64, linux/ppc64le, linux/s390x, linux/386, linux/mips64le, linux/mips64, linux/arm/v7, linux/arm/v6Labels: org.mobyproject.buildkit.worker.executor: oci org.mobyproject.buildkit.worker.hostname: docker-desktop org.mobyproject.buildkit.worker.network: host org.mobyproject.buildkit.worker.oci.process-mode: sandbox org.mobyproject.buildkit.worker.selinux.enabled: false org.mobyproject.buildkit.worker.snapshotter: overlayfsGC Policy rule#0: All: false Filters: type==source.local,type==exec.cachemount,type==source.git.checkout Keep Duration: 48h0m0s Keep Bytes: 488.3MiBGC Policy rule#1: All: false Keep Duration: 1440h0m0s Keep Bytes: 24.21GiBGC Policy rule#2: All: false Keep Bytes: 24.21GiBGC Policy rule#3: All: true Keep Bytes: 24.21GiB

[crazy-max]

Atm it returns GC Policies and labels only for the default worker.

[jedevc]

Hm, this does make the output a bit noisier, and the policies are slightly tricky to mentally parse. I wonder if the GC policies should be hidden behind a verbose flag? Not sure about this, it's definitely useful information, but probably not to the average user.

I think the labels should be good without that, they're not too long.

[crazy-max]

Hm, this does make the output a bit noisier, and the policies are slightly tricky to mentally parse.

Yeah that's noisy but still relevant and for parsing we should do smth like #830 (comment)

I will move Platforms before Labels.

[jedevc]

LGTM, but we should make sure to get the follow-up to tidy the output and parsing into the same release as this.

[crazy-max]

Yes and also another follow-up for our actions toolkit: https://github.com/docker/actions-toolkit/blob/8cb1698b203083ee1c3996cbd2a0d197cae79d9f/src/buildx/builder.ts#L57

[jedevc]

@crazy-max@tonistiigi, anything blocking this?