Fix handling of cloud tags in go publish

[blink1073]

Addresses this bug:

https://github.com/mongodb/mongo-go-driver/actions/runs/11218783286/job/31183817541

gh release create vcloud-1.17-cloud2 --draft --verify-tag --title 'MongoDB Go Driver cloud-1.17-cloud2' -F /home/runner/work/_actions/mongodb-labs/drivers-github-tools/v2/golang/publish/github.md
[480](https://github.com/mongodb/mongo-go-driver/actions/runs/11218783286/job/31183817541#step:4:491)
~/work/mongo-go-driver/mongo-go-driver ~/work/_actions/mongodb-labs/drivers-github-tools/v2/golang/publish
[481](https://github.com/mongodb/mongo-go-driver/actions/runs/11218783286/job/31183817541#step:4:492)
tag vcloud-1.17-cloud2 doesn't exist in the repo mongodb/mongo-go-driver, aborting due to --verify-tag flag

[blink1073]

Closing, as we're supposed to be using the format x.y.z-cloudn for these tags.