.github: Add flatcar_production_qemu.sh to generic image zip

When downloading the generic image to run a test it would be nice to
have the qemu script in the zip bundle.

Author: pothos

.github/workflows/ci.yaml

@@ -279,6 +279,7 @@ jobs:
             scripts/artifacts/images/flatcar_production_image*.json
             scripts/artifacts/images/flatcar_production_image_pcr_policy.zip
             scripts/artifacts/images/flatcar_production_*_efi_*.fd
+            scripts/artifacts/images/flatcar_production_qemu.sh
 
       - name: Upload developer container
         uses: actions/upload-artifact@v4