Potential fix for code scanning alert no. 144: Workflow does not contain permissions

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

Closes scylladb/scylladb#27809

.github/workflows/docs-pages.yaml

@@ -18,6 +18,8 @@ on:
 
 jobs:
   release:
+    permissions:
+      contents: write
     runs-on: ubuntu-latest
     steps:
       - name: Checkout