Apply suggestion from @paulinebm

Author: paulinebm

.github/workflows/claude_review.yml

@@ -34,7 +34,7 @@ jobs:
       cancel-in-progress: true
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd #v6.0.2
         with:
           fetch-depth: 1