Use Go 1.17 in CI

[fredrikaverpil]

Why?

If I'm not mistaken, the idea is that Sage should be compatible with Go projects
written with Go 1.17, given the contents of the go.mod file:

https://github.com/einride/sage/blob/master/go.mod#L3

However, there is code in the repo which requires newer Go versions.

What?

• Use Go v1.17 in CI, so to surface the warnings/errors which needs fixing.
• Do not use errors.Join (introduced in Go 1.20)
• Do not use math/rand/v2 (introduced in Go 1.22)
• ...

Notes

• Related; we might opt for upgrading the minimum required Go version instead: Require Go 1.22 from now on #648