dev/ci: set direct as goproxy fallback
Created by: bobheadxi
idk how this took me so long but I eventually found https://go-review.googlesource.com/c/go/+/226460/ and some usage examples: https://sourcegraph.com/search?q=context:global+GOPROXY%3D%22.*%28%2C%7C%5C%7C%29direct%22&patternType=regexp
Test plan
gonna run main-dry-run a few times