Potential fix for code scanning alert no. 1: Workflow does not contain permissions

Co-authored-by: Copilot Autofix powered by AI <62310815+github-advanced-security[bot]@users.noreply.github.com>

Author: abdolence

.github/workflows/security-audit.yml

@@ -6,6 +6,8 @@ on:
       - '**/Cargo.lock'
   schedule:
     - cron: '5 4 * * 6'
+permissions:
+  contents: read
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref_protected && github.run_id || github.event.pull_request.number || github.ref }}
   cancel-in-progress: true