Default version should be up-to-date

[Tethik]

Current default version is set to a version that is now EOL
https://github.com/einride/sage/blob/master/sg/makefile.go#L18
https://github.com/einride/sage/blob/master/actions/setup/action.yml#L18

In the short term this should be bumped to a newer version (e.g. the current latest - 1.25.3).

Long term it would also be good to consider:

• How Makefiles that are generated and how to avoid pinning an outdated version in them.
• How to avoid go-version usage in the github action from becoming stale the same way.
• The github action would also be more user-friendly in terms of less maintenance if it defaulted to using the go.mod (or go.work) version.