Replace the packer-images gobuilder with a Dockerfile matrix built on each
container-base distro image, on a single repo semver.
- install golang, gcc and nfpm
- bake the sha256-pinned go-cache-plugin v0.1.0 binary onto PATH
- run in-image assertions as a --target test build stage
- add pull_request build/test/pre-commit and tag-triggered docker workflows
unkin-agent
gitadmin