Imports of package exporter

PathSynopsis
contextPackage context defines the Context type, which carries deadlines, cancellation signals, and other request-scoped values across API boundaries and between processes.
github.com/moby/buildkit/cache
github.com/moby/buildkit/solver/result
github.com/moby/buildkit/util/compression
github.com/opencontainers/image-spec/specs-go/v1