workaround a regression in 1.11.3

> We are aware of a functionality regression in "go get" when executed in GOPATH mode on an import path pattern containing "..." (e.g., "go get github.com/golang/pkg/..."), when downloading packages not already present in the GOPATH workspace. This is issue golang.org/issue/29241. It will be resolved in the next minor patch releases, Go 1.11.4 and Go 1.10.7, which we plan to release soon. We apologize for any disruption.