ci: remove GOPROXY environment variable due to https://github.com/go-yaml/yaml/issues/887
ci: remove GOPROXY environment variable due to https://github.com/go-yaml/yaml/issues/887

Signed-off-by: Samuel Karp <97468ec0e303d67c50f7bb93576f42916fd517d7@google.com>

thaJeztah/containerd,estesp/containerd,containerd/containerd,containerd/containerd,mikebrow/containerd,mikebrow/containerd,estesp/containerd,thaJeztah/containerd