GitHub Actions CI: Status not reported from forked PRs

[kwin]

In case the PR was raised from a forked repository the Github action run after previous approval but doesn't report the status (necessary for the required checks). This can be seen in #2651 where the GitHub action was successfully executed in https://github.com/Adobe-Consulting-Services/acs-aem-commons/actions/runs/1052117286 but the status not reported back.

The same is true for the Codeclimate check.

[kwin]

Further hints in https://docs.github.com/en/actions/reference/events-that-trigger-workflows#pull-request-events-for-forked-repositories-2 and https://docs.github.com/en/actions/reference/authentication-in-a-workflow#modifying-the-permissions-for-the-github_token and https://securitylab.github.com/research/github-actions-preventing-pwn-requests/.