message: Restrict regex to commented lines
diff: @@ -21,7 +21,7 @@ jobs:
  - name: copyright check
  run: |
  cd MFEM
  - if git grep -l "\-2020" > matches.txt
  + if git grep -l "^#.*\-2020" > matches.txt
  then
  echo "Some files with outdated copyrights were found."
  echo "Please update to 2021. Here is the list:"
  