Dockerfile: don't use intermediate "deploy-source" stage
Dockerfile: don't use intermediate "deploy-source" stage

The "deploy-source" stage was added in a previous refactor. While
this stage is useful to "export" all docs (including archives if
needed), and _convenient_ to collect all those files to the final
stage, it caused a regression in performance.

This patch changes the final ("deploy") to copy the "archives" and
"current" docs separately, so that the archived versions can be
cached in the final stage, and don't have to be copied again on
each rebuild.

Signed-off-by: Sebastiaan van Stijn <64b2b6d12bfe4baae7dad3d018f8cbf6b0e7a044@gone.nl>

docker/docker.github.io,docker/docker.github.io,thaJeztah/docker.github.io,thaJeztah/docker.github.io,docker/docker.github.io,thaJeztah/docker.github.io,docker/docker.github.io,thaJeztah/docker.github.io,docker/docker.github.io,thaJeztah/docker.github.io