fix: Add permissions to action (#106)

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

Author: nlogozzo

.github/workflows/spelling.yml

@@ -5,6 +5,8 @@ on:
     branches: [ "main" ]
     types: [ "review_requested", "ready_for_review" ]
 name: Spell Check
+permissions:
+  contents: read
 jobs:
   codespell:
     runs-on: ubuntu-latest