Potential fix for code scanning alert no. 3: Workflow does not contain permissions

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

Author: NafisianCastle

.github/workflows/dependency-update.yml

@@ -1,5 +1,9 @@
 name: Dependency Update
 
+permissions:
+  contents: read
+  pull-requests: write
+
 on:
   schedule:
     # Run every Monday at 9 AM UTC