The release-go build is the last step for each version-specific release, and the release-go-images build is the final step for the day's overall release. If these builds succeed, it's expected that no more steps are necessary for their associated tracking issue. Closing them is a good indication to the dev running the release that a step is done. If the dev notices something didn't go right (even though automation thinks it went fine), they can reopen the issues.