Potential fix for code scanning alert no. 1: Workflow does not contain permissions (#334)

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

Author: garloff

.github/workflows/link-validator.yml

@@ -1,5 +1,7 @@
 on: [pull_request]
 name: Check links for modified files
+permissions:
+  contents: read
 jobs:
   markdown-link-check:
     runs-on: ubuntu-latest