workflow checking for diffs fails even if no diffs

[eriknordmark]

The check for differences seems to result in exit 1 even if there are no changes (see below), and reading the code it will definitely exit 1 if there are tool version changes.

0s
Run echo "changed and uncommitted files, excluding versions"
changed and uncommitted files, excluding versions

differences other than tool version changes:

differences including tool version changes:
Error: Process completed with exit code [1

From https://github.com/lf-edge/eve-api/actions/runs/5960807127/job/16168787320?pr=19#step:4:1