Deploys no longer depend on Docker.
With only Make and gcloud installed, the following should deploy a new version:
$ git clone https://go.googlesource.com/tools
$ cd tools
$ cd cmd/godoc
$ make cloud-build deploy
Updates golang/go#27205.
Change-Id: I5cc1142e02dc288450d55dbd4da4b30c0a080bd5
Reviewed-on: https://go-review.googlesource.com/c/139240
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>