go test ./src/test/
See how-to-use-a-private-go-module,
or stackoverflow,
in particular, set the "instead of credentials" in ~/.gitconfig by adding the following line:
[url "https://YOURUSERNAME:YOURTOKEN@github.com/"]
insteadOf = https://github.com/
and set the environment variable
export GOPRIVATE=github.com/D8-X/d8x-futures-go-sdk/
Then you can upgrade via go get github.com/D8-X/d8x-futures-go-sdk@latest