ci(workflow): add test-unit to required checks

[vtsvetkov-splunk]

Issue number: -

Summary

Github actions marks jobs as succeeded if it failed with continue-on-error. There is no other way to check if jobs were actually failed. That the reason why adding test-unit to all-checks did not have any effect.

Changes

Add output variable for every continue-on-error jobs that helps to identify failed ones during all-checks. You might check the result when tests are broken: https://github.com/splunk/addonfactory-ucc-generator/actions/runs/9365665879/job/25782687764#step:3:1

User experience

No impact

Checklist

If your change doesn't seem to apply, please leave them unchecked.

• I have performed a self-review of this change
• Changes have been tested
• Changes are documented
• PR title follows conventional commit semantics