Merge branch 'sh-update-go' into 'main'

Update to Go 1.21.8

See merge request https://gitlab.com/gitlab-org/ci-cd/docker-machine/-/merge_requests/123



Merged-by: Axel von Bertoldi <avonbertoldi@gitlab.com>
Approved-by: Axel von Bertoldi <avonbertoldi@gitlab.com>
Co-authored-by: Stan Hu <stanhu@gmail.com>