chore(setup): Assume availability of registry mirror in more cases (#6682)

* chore(setup): Assume dependabot can access registry mirror

* Apply suggestion from @davidkna-sap

* Apply suggestion from @davidkna-sap

Author: davidkna-sap

.github/actions/setup/action.yml

@@ -51,7 +51,7 @@ runs:
       env:
         REGISTRY_URL: ${{ inputs.registry-url }}
         REGISTRY_TOKEN: ${{ inputs.registry-token }}
-        IS_FORK: ${{ github.event_name == 'pull_request' && github.event.pull_request.head.repo.owner.login == 'sap' && 'false' || 'true' }}
+        IS_FORK: ${{ (github.event_name != 'pull_request' || github.event.pull_request.head.repo.owner.login == 'sap' || github.event.pull_request.user.login == 'dependabot[bot]') && 'false' || 'true' }}
       shell: bash
       run: |
         if [[ -n "$REGISTRY_URL" ]]; then