fix: use PAT to delete existing cache

.github/workflows/update-vulnerability-database.yaml

@@ -37,7 +37,7 @@ jobs:
               gh cache delete "${CACHE_ID}"
           done
         env:
-          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          GH_TOKEN: ${{ secrets.CLOUD_SDK_AT_SAP_ALL_ACCESS_PAT }}
 
       - name: Cache CVE Database
         uses: actions/cache/save@v4