let's run only, where we have API key available (#667)

## Description

mend scans on forks are never successful
e.g.
https://github.com/hilmarf/ocm/actions/runs/7945515639/job/21692267352
`-apiKey $API_KEY` is of course missing

So maybe we should consider NOT to trigger scan from forks?

## What type of PR is this? (check all applicable)

- [ ] 🍕 Feature
- [ ] 🐛 Bug Fix
- [ ] 📝 Documentation Update
- [ ] 🎨 Style
- [ ] 🧑‍💻 Code Refactor
- [ ] 🔥 Performance Improvements
- [ ] ✅ Test
- [x] 🤖 Build
- [x] 🔁 CI
- [ ] 📦 Chore (Release)
- [ ] ⏩ Revert

## Related Tickets & Documents

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> Remove if not applicable

## Screenshots

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## Added tests?

- [ ] 👍 yes
- [ ] 🙅 no, because they aren't needed
- [ ] 🙋 no, because I need help
- [ ] Separate ticket for tests # (issue/pr)

Please describe the tests that you ran to verify your changes. Provide
instructions so we can reproduce. Please also list any relevant details
for your test configuration


## Added to documentation?

- [ ] 📜 README.md
- [ ] 🙅 no documentation needed

## Checklist:

- [ ] My code follows the style guidelines of this project
- [ ] I have performed a self-review of my code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] I have made corresponding changes to the documentation
- [ ] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] New and existing unit tests pass locally with my changes
- [ ] Any dependent changes have been merged and published in downstream
modules

Co-authored-by: Gerald Morrison <[email protected]>

.github/workflows/mend_scan.yaml

@@ -25,6 +25,7 @@ on:
         - debug
 jobs:
   mend-scan:
+    if: github.repository == 'open-component-model/ocm'
     runs-on: ubuntu-latest
     permissions:
       pull-requests: write