ubuntu-latest does not contain sbt

[googley42]

this causes the documentation GHA to fail

Run sbt  +publishLocal
/home/runner/work/_temp/34054862-03fd-420d-8c5c-3[7](https://github.com/zio/zio-schema/actions/runs/11349900676/job/31567077417?pr=751#step:4:8)7bcdfa453c.sh: line 1: sbt: command not found
Error: Process completed with exit code 127.

see actions/runner-images#10767

I think fix is to pin ubuntu to a recent version that contains sbt
ignore this statement about a fix - for proper one see @plokhotnyuk comment below

[plokhotnyuk]

@googley42 The following task solves missing sbt command (instead of Ubuntu version pining):

        uses: coursier/setup-action@v1
        with:
          apps: sbt

[googley42]

closed by #761