Update auto_review_documentation.yml

Author: chienyuanchang

.github/workflows/auto_review_documentation.yml

@@ -40,7 +40,9 @@ jobs:
       - name: Get changed files
         id: changed-docs
         run: |
+          # Retrieve list of files changed between the previous commit and the current SHA
           git diff --name-only ${{ github.event.before }} ${{ github.sha }} > changed_files.txt
+          # filter to include only documentation files
           grep -i -E "${DOC_FILE_FILTER}" changed_files.txt > changed_docs.txt || > changed_docs.txt  # -i ignore case
 
           echo "Files changed with DOC_FILE_FILTER (${DOC_FILE_FILTER}) — could be empty:"