Dockerfile: build gotestsum from source
Dockerfile: build gotestsum from source

Building form source is slower, but will support other architectures, such as arm64

Before:

     => [gotestsum 1/2] ADD https://github.com/gotestyourself/gotestsum/releases/download/v0.4.0/gotestsum_0.4.0_linux_amd64.tar.gz gotestsum.tar.gz  2.3s
     => [gotestsum 2/2] RUN tar -xf gotestsum.tar.gz gotestsum -C /go/bin                                                                             1.8s

After:

    => [gotestsum 1/1] RUN go get gotest.tools/gotestsum@v0.4.0                                                                                       13.0s

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

cpuguy83/cli,thaJeztah/cli,cpuguy83/cli,docker/cli,thaJeztah/cli,docker/cli