Improve notebook change detection in workflow

Author: brown9804

.github/workflows/render-notebooks.yml

@@ -45,10 +45,14 @@ jobs:
       - name: Check for changes
         id: git-check
         run: |
-          if [[ -n "$(git status --porcelain **/*.ipynb)" ]]; then
-            echo "has_changes=true" >> $GITHUB_OUTPUT
-          else
+          # More reliable way to check for changes in notebooks
+          git update-index --refresh
+          if git diff-index --quiet HEAD -- "*.ipynb"; then
+            echo "No changes detected in notebooks"
             echo "has_changes=false" >> $GITHUB_OUTPUT
+          else
+            echo "Changes detected in notebooks"
+            echo "has_changes=true" >> $GITHUB_OUTPUT
           fi
 
       - name: Show modified files